I got a pair of those, apart from looking like a fool, they keep the rain out perfectly. Only trouble is they steam up a little when stationary. Clears up pretty quickly though. And whoever says the vented lenses are better, they used to steam up too on my jawbones just not as much.
I got a pair of Oakleys Wind jacket and the rubber rim (that you can remove) stops most of the rain. Works a treat for me