I picked up running recently, and with softball season kicking off, I decided I needed a good pair of sport glasses for both activities (beach use is not out of the question either).  I grabbed the Tifosi Slips due to good reviews, good price (about $12 off MSRP and $6 less than the cheapest store price I saw) with the Extreme Contrast, GT, and Brown one-piece lenses.

The build quality of the frame seems to be pretty sturdy, and it does seem to give a bit (it has to in order to replace the lens) without damaging integrity (though I wouldn't dare go so far as all the beds and twists demoed on the Tifosi website).  As for the lenses, they are supposedly made of shatter-proof plastic, but that's a point that I hope I never have to prove with a real-world test.  The earpieces are adjustable/bendable, but, again, I'm not testing it and don't foresee a real need for that ability based on my own activities.

Changing the lenses isn't super easy.  That's good, because it means the lenses won't randomly come loose or fall out.  On the inverse, I always feel like I'm going to break either the frame or the lens, especially when removing the lens.  The other not-so-great part is that unless you are wearing gloves while doing so, you are bound to get a bunch of fingerprints on the lens while replacing.  Just a PITA to have to keep cleaning them each time.

Regarding the lenses, I must admit that I am happy.  I have yet to use/test the EC lens.  The other two perform admirably, but oddly enough, I feel that the brown lens gives things a 'sharper' look than the GT lens (which, by explanation, should be sharper).  Will have to test that out a bit more.  Also, a slight annoyance is that the lenses aren't marked.  The red EC was easy to pick out, but the other two are mildly similar.  You still have to go to the website to figure it all out (and the website isn't all that specific or exact).  The only guide that came with the glasses was how to replace the lens.  That's it.  Regardless, the view out of each lens is 100x better than anything you'd find on a drug store turn-style, and comparable to the pay-for-the-name brands of sports glasses we're all familiar with.

The reason I did buy these is because I needed a set of sport glasses that weren't polarized/wouldn't skew my view and that wouldn't fog up.  They pass the first qualifier with flying colors.  The second...let's say they get a B.  Better at not fogging than other glasses (I assume the built-in vents help), but once in a while a fog spot will form.  Doesn't stick around long, but if it happened at a bad time (at bat trying to hone in on a pitch) it could be an issue.  It's only happened a couple times, so I'll reserve worse judgement for the time being.

The hard shell case is a nice extra, as is the soft case as well (that can second as a lens wipe in a jam).  The accordian-style removable lens holder in the hard case is also a nice bonus as well, keeping it all in on location.

I am happy with these thus far, and expect the experience to continue based on the initial findings.