Okay, this is going to be a comprehensive underwear review.  Not something that I have done before, but I'm hoping it will be helpful to someone.  My goal is to provide my personal opinion about fit, comfort and performance.  This is a review about men's underwear though, including thongs, so I am going to try to keep the discussions clinical but informative.  If you believe you may be offended by this topic, please, do not read any further.  Thank you.

Every male is going to be built differently, so let me explain my situation and why it became so important for me to find "the right underwear."  I have a 37.5" hip measurement and a 38.25" waist (at the belly button) measurement.  All the underwear I have tried is size "large."  I originally tried to wear boxers and boxer briefs, but they became unacceptable in a professional setting.  I switched to briefs, but then found them to be too restricting.  I needed to find underwear that gave me support throughout the day, but also were roomy enough to accommodate my volume.  I honestly believe that male underwear should have a variety of sizes just like women's bras have.  Unfortunately, no man would ever admit that he wears a 38AA underwear, so I guess that isn't going to happen anytime soon. Ha!

The seven pairs I will be reviewing are:
Hanes Classics Men's 3-Pack Full Rise Brief
Hanes Fashion Mid-Length Briefs 5-Pack
Hanes Men's Seamless Pouch Brief (Discontinued?)
Gregg Homme Men's Black Push Up Padded Thong Size Large
Calvin Klein Men's Body Hip Brief, Black, Large
Calvin Klein Men's Body Thong, Black, Large
Papi Men's 3-Pack Cotton Thong In White, White, Large

Hanes Classics Men's 3-Pack Full Rise Brief

These are an economical purchase.  They are what I consider to be the average cotton brief.  The pack came in cool shades, none were white.  The waistband and other materials were pretty comfortable.  The crotch on this underwear is designed for a Ken doll though.  My body would not fit comfortably in these.  The restriction caused an asymmetric arrangement which, during certain movements, would be uncomfortable.  The lack of sufficient cup design caused the gussets to remain elevated off of the body, which in turn causes occasional rubbing and irritation to the upper thigh.  Overall, these are "default underwear."  2 STARS

Hanes Fashion Mid-Length Briefs 5-Pack

These are also an economical purchase.  They were better than the previous default underwear in that the materials were even softer, and the waistband was low enough to allow for no underwear to be seen while wearing certain jeans.  Unfortunately, this underwear suffers the same drawbacks that the Hanes Classics Men's 3-Pack Full Rise Brief did; there is just no considerations taken for large male anatomy.  The gussets again, would not lie against the leg, causing occasional irritation, and the material was so restrictive that it caused asymmetric arrangements that were occasionally uncomfortable.  Overall, these are "better, but not great." 3 STARS

Hanes Men's Seamless Pouch Brief (Discontinued?)

So, I found these pairs on Hanes' website some time ago.  They were so comfortable, that I own over half a dozen of these.  They are spandex-like material, and the crotch is cupped to provide a pouch to give support and symmetry.  All the material is very soft and comfortable all over.  Unfortunately, it is not without drawbacks.  Besides being rare to find and possibly discontinued all together, this underwear has an obscenely high waistband.  It easily goes over my belly button and is labeled with a gigantic "Hanes" logo right in the front.  Now, I do not have washboard abdominals, so on top of everything, my bellow, however minor, causes the material to roll down.  This causes a very mild discomfort, especially while wearing pants that are tight in the waste.  By prefolding the underwear down, I can make a satisfactory adjustment.  Overall, this underwear has been my "long-standing favorite."  4 STARS

Gregg Homme Men's Black Push Up Padded Thong Size Large

Okay, first I will say that this is the first thong I have ever worn, so let me give you a man's opinion on just that first.  On occasion, I have had briefs bunch up and it would require me to make a wardrobe adjustment.  Typically this would be important while wearing professional or evening dress attire, and would involve positioning myself near a wall and doing a slight shift dance so it doesn't look like I'm "just picking."  Now, when I first wore the thong that is the same feeling I had.  I felt compelled to shift and adjust in an attempt to fix my garments.  After some hours of wearing it though, it began to feel more natural.  While walking, the thong feels just fine.  If anything, it feels most uncomfortable while sitting.  If I do an extreme slouch, it feels fine, and if I sit up all prim and proper, it feels fine.  Slouching, just a little though, makes the material tighten down on my coccyx, which causing unfamiliar discomfort.  Being forced to sit up more straight was not something I expected from a thong design.  Now, the rest of the underwear, on the hips and waist, is quite comfortable.  The material is rather thin, but nothing roles down.  Everything stays where it should.  Finally, the crotch design: this underwear has a padded cup, which I was expecting to be something ridiculous, but in actuality, it is quite sensible.  It reminds me of the form material in a bra.  Not so much padded to give you the illusion of extra size, but more preformed for shape.  It feels akin to wearing a costume, like a codpiece.  My body is comfortably symmetric within the cup.  My only complaint is that the cup is not large enough to retain my volume and keep the gussets on the skin.  Again, I have that occasional irritation when the thigh meets the gusset.  If the cup was larger, it would be perfect.  For a man of a different shape, this underwear may be perfect.  Overall, I would say these are "new and interesting, but could use improvement."  4 STARS

Papi Men's 3-Pack Cotton Thong In White, White, Large

Alright, here I have the Papi set.  These win out over the Gregg Homme in multiple ways.  1.) They come in a three-pack for about the same price.  2.) They are significantly more comfortable!  3.)  The pouch is much larger.  The gussets lay flat and do not shift.  Everything is held in place quite nicely.  I love them!  There is one bad thing though.  They are ugly!  Definitely look like a jock strap or a weird pair of whitey-tighties.  So comfortable though!  I never once thought about them, from the moment I put them on and went about my day.  They were perfect.  They will make great everyday wear.  Overall, I would say these are "everyday underwear." 4 STARS

Calvin Klein Men's Body Thong, Black, Large

These are almost as comfortable as the Papi brand.  They definitely look better than those jock straps.  Unfortunately the Calvin Klein are sold in singles.  They have all the same benefits that Papi have in fit and comfort, but I can feel the back a bit more.  It isn't bad.  Just kind of there, you know?  Overall, I would say these are "the evening wear underwear." 4 STARS

Calvin Klein Men's Body Hip Brief, Black, Large

Well, this Calvin Klein was not what I expected.  It is a cotton brief with a very well defined and comfortable pouch.  The waistband is great; in fact, all over, the underwear is comfortable.  The problem is the backside is too voluminous.  I don't have a backside like a linebacker, but my bum isn't flat as a board either.  The underwear is formed to fit a much rounder bottom, and so it is exceptionally saggy.  They are definitely not for dress pants.  I'm wearing them with kakis, and they seem to be okay.  These pants are not the tightest I have.  Definitely wouldn't want to wear them with tight pants unless you want a bunchy diaper effect.  These would probably be very comfortable with jeans while doing manual labor.  In fact, I have to say that comfort is the number one plus with this pair.  Unfortunately, they are not cheap, being sold only in singles.  Overall, I'm pretty disappointed in them.  If they were half the price or if you have a lot of booty, these underwear will be a good buy.  They have quality, just not shaped properly for me.  Overall, I would say these are "overly expensive work underwear." 3 STARS

So, there we have it!  I was really hoping the CK Hip Briefs would have replaced my "long-standing favorite" but I'm surprised to see that award going to the Papi 3-Pack.  They are definitely the most economical/comfortable combo.  They do lack quite a bit of style, so I wouldn't wear them for an evening out.  The CK thong has the most style, sacrificing a little comfort and a lot of coin.  The Gregg Homme was definitely the most gimmicky.  Having never worn a thong before, it does not give a good first impression.  It isn't nearly as comfortable as the others.  It wasn't so bad that I would throw them out outright, but I won't be buying another pair.  The Calvin Klein Hip Briefs were the most disappointing.  They feel great and fit well in the front, but the back is just horrible.  I won't be buying any more anytime soon.  Maybe after rounding out the posterior with some squats.  The three Hanes underwear pairs are definitely out.  The seamless pouch is hard to find and the waistband is way too high.  The other two are just not comfortable unless you're a Ken doll.  The Papi are definitely going to be the next ones on my wishlist.  I'm pretty satisfied with them, and I could see them being my everyday underwear.

I hope this review was helpful to someone.  Every man is going to be different, so I wanted to give enough detail to help you decide.  None of these pairs were of "bad quality," they just have their little pros and cons.  If you have any questions, I would be happy to respond.