Because that's what everybody will be doing to you when you're sporting these puppies.
Probably not really, but they do look great! I see a lot of people complaining that the lenses tend to crack on the corners where you lock in the frame. I've been using mine for 5 or so months, and they have not yet started doing this. I can see how the lenses could be a bit weak there, though.
Switching out lenses is a breeze! Mine came with 2 lenses, one for sunny conditions and one for low light conditions. The nose piece is also adjustable, so it should fit comfortably no matter what! I have a smaller, narrower face and these fit great! We also have the Arena Max if you have a larger face and think you would benefit from the larger lens.
I can't really tell if the Chromapop technology makes too much difference, but I would probably still splurge for it. I imagine I'd miss it if I went back to some standard lenses.
I don't really have any complaints what so ever. These perform awesome, and I tend not to even notice them after I put them on!