I spend all winter on the snow working. I go through A LOT OF GEAR. All I can say about these are they are amazing AMAZING. The Fit is great (the are big but so am I)they fit perfectly with a Giro G9 helmet, and for once a company has an anti-fog that actually keeps goggles from fogging. As far as the lens auto tint goes, I don't know how I have skied with out it. You forget you are wearing goggles. They are the best there is.
Cons: The lens is held on with the triangle clips around the frame, so when you take them off or need to pull them over your helmet you need to make sure you don't pull on the lens. If you do it can come on clipped in a few spots. So, just grab them by where the strap attaches and you should be good to go!
Over all: Buy these or another SPPX lens goggle from zeal. The auto-tinting lest may seem a bit over the top but it is 100% worth it!