This question gets asked a lot both on line and on the phone.
I switched to an open face helmet 5 years ago and once I tried a lot of goggles I finally found the ones that work.
Most important is the goggle/helmet fit and the balaclava you wear to keep you warm.
509 goggles are hands down the best goggle for midwest riding, they were designed to be a snowmobile goggle not a dirt goggle with dual lenses. Sinister2 509's work Aviator 509's DO NOT. If you notice on our website we don't even offer the Aviators because they fog real easy.
Helmets - Many to choose from, ventilation is key. I've ridden in a HJC (good), Fly (good) and Klim F4 (great). Guys in my group are riding in 509, HJC, Fly and Scorpion which all accept the 509 really nice. You want the goggle to seal up on the sides and top so there are no air gaps allowing exposed skin.
Balaclavas - Klim Covert is the best that I've used, covers up over your nose, Gore-Tex windstopper material and high quality.
As far as value goes I would recommend the following:
509 Helmet/509 Goggle/Klim Covert head sock Combo for $279.90
Highest quality, best ventilation combo:
Klim F4 helmet/509 Goggles and Klim Covert head sock $504.99 for the whole package. Not cheap but something you'll have until you WANT something new.