I see what your saying, the deflector is there to stop it like you said, but for quad riding I really don't think it would matter, but on a bike... I certainly know what you mean.
Anyone know how waterproof these will be?
They sure are warm, after a quick 22 mile ride my feet were toasty.
Funny thing about MX (or enduro for the matter) boots is they don't seem to be designed to be waterproof. First time I used my Astars my feet got soaked.
Of course it doesn't help when your hitting puddles hard enough to blow your feet off the pegs

They seem to have gotten more water resistant with use? I have never put anything on them to aid water resistance so double....??
I have found lightweight WOOL socks work best in hot to cool temperatures. You don't need to spend big bucks on MX socks, just get a few good pair of Colombias or something similar. The wool socks I wear are actually heavier than the cotton work socks I wear daily but they keep my feet cooler and drier.