This item must excel at what I understand it was designed for. That is, military HALO jumps. They will also work well as motorcycle goggles, parasailing, hang gliding, ATV'ing. Any activity where you need eye protection and keep moving forward is just made for this guy. I'll give them four stars.
That motion thing is the important part. You need that to keep air circulating through the holes in the lens so as to avoid fogging of the lens. I was shown this item at an Airsoft store in California and was told they were wonderful for Airsofting. They certainly looked the part, with a thick, tough-looking lens and big air holes and the fact that they were sold out except for the display gave me the idea they must be very popular. I think the salesman must play a lot of Rush-style games, though, where he's running forward because when my son put the goggles on to play they fogged up pretty quickly. He'd stop to reload or start sniping and they'd fog right up.
I have found that all it takes is the act of walking briskly forward to keep them clear so I don't fault the design. I even wore them on a long bicycle ride to see how they reacted to the wearer being REALLY hot and sweaty. Great during the ride but they fogged immediately when I stopped.
Long story short: great product, don't wear for Airsoft. It's a good thing I have a motorcycle so I can get some use out of them. Heck, I may get the smoke lens next time I need daytime goggles, they're so good.
Addendum: Changed to five stars. I gave it four stars but, really, it's a five star item that I bought for the wrong purpose and I shouldn't blame Smith Optics for that. Got a suggestion for goggles with good ventilation for indoor play? Please let me know!