I have 3 radbots. Two of them are on a winter bike and they see all kinds of weather. The other one was on my all-weather commuter until I got dyno lights. Both are about 3 years old and work well.

My Cygolight Hotshot is also on my winter bike, out of the slop a little more but it's seen rain. The thing I don't care for on it is the USB plug has starting working loose on occasion (I don't know what would happen if it got rained on in that condition) and it's harder to turn off with gloves on. For summer use it would probably be fine.