These gloves are pretty great. I used them for riding all winter through cold rain and light snow, followed by a 2400 mile tour through British Columbia, Yukon, and Alaska with temps down to the 20s and 30s.
The gloves would get wet on the inside pretty reliably, probably moreso from sweat than rain. This is certainly not optimal but after trying many types of gloves I'm convinced this is inevitable with this amount of insulation and waterproofing. As long as you maintain light to moderate exertion you will keep the gloves warm despite being wet. I found the liners not to be all that great, but I don't really see the need for them. For warmer temps I wear the Pearl Izumi softshell lite gloves.
Dexterity is as good as you can get for a glove this warm. It was possible albeit clunky to operate my point and shoot camera with these gloves and while riding.
At the end of the day, if you're going to be riding in seriously nasty weather I would highly recommend these gloves for keeping your digits intact.