Pros:
-designed well to fit multiple sizes
-tail is more colorful than pictured and looks amazing, better than pictured
-there is a stretchy panel in the back of the corset which allows it to adjust from size 2-6 and still have a fitted look
-the best mermaid top I have seen that covers your midriff but still looks sexy and cohesive with the costume
-the base of the tail part is very full and made with nice material(each layer is a different shade giving it visual texture and a translucent fish like quality)

Sizing:
I was very worried about sizing I am usually a small/medium and a 6/8 depending on the brand and wasn't sure what to with xs/s and M/L sizes. I am also fairly busty and curvy.(D) My measurements matched the xs/s and I wanted a fitted look so I went with xs/s.  It fits great and doesn't feel uncomfortable I did have a mishap with the top (See below). There is still plenty of room in the boob part or not a lot of support which leads me to believe most of us will need a strapless bra underneath. I love how it fits me, fitted but I think if I was 5-10 lbs heavier it probably would be too tight.(I currently weigh 140 at 5'5" I am also hourglass shaped so not sure if that makes a difference) I can sit comfortably, touch my toes, and squat without worrying about overstretching or splitting a seam.

Cons:
-sea shell accent on hip is a little mushed when you take it out of the package;(to be expected after shipping) easily fixed by hanging and fluffing
-WARNING: DO Not Pull Corset Over Your Head, like I did.  While the seams are well sewn and the top stretchy, the translucent overlay material in the bodice pulls out of the seams easily and unravels. I highly recommend taking the time to undo the laces and put it on the slow way. (fairly confident this is because the translucent overlay unravels easily at the ends, I am right on the verge of either size- but I wasn't any rougher in pulling it over my head than I would be with a shirt or nightgown.)
If The Delicate Corset Overlay Does Split or Pull From The Seam, I fixed this by pulling all of the translucent layer off of the blue part of the corset.  The blue underneath is very pretty by itself and would accent the tail and big shells nicely. I wanted it to sparkle so I covered the newly exposed blue section with one of those $1 cans of silver sparkly glitter hair spray they sell at halloween and covered that with a thick layer of normal hair spray to keep the glitter from flaking everywhere.
-the sea shells are quite large which might be problematic if you are small busted.

Other notes:
-the shells do stand out as pictured
-what you cant really see in the pic is that one side has a blue/green strap on the left side- that matches the tail poof. the other side has a clear strap.  If you aren't into the asymmetrical straps you can easily remove the green part of the left strap (its material over a clear strap)

Overall I am very happy with the costume despite the mishap.