All of those covers look like they would cover my Blackburn Flea light that I wear on my helmet, so I would stick with what I use now: a hood (from my O2 rain jacket) under the helmet. If it's much over 45 degrees I would be inclined to just let my hair get wet.

I like my helmet visor but I don't think any of them are long enough to keep rain off my glasses at 35 mph which I hit on the downhill side of my ridge. I wear contact lenses in the rain. My optical correction is about minus 11 diopters, so wet glasses mean I'm blind.