I wear Klim Togwotee gloves and my hands stay warm and dry, largely due to the inner layer. My biggest complaint is that when the outer shell gets wet, (and they will if you have to dig...hmmmm...think I found my problem!), if it's cold, the leather ices up and it's sometimes hard to hold on. At least until the grip warmers melt the ice!
Some of my friends don't like the two part construction because they can be difficult to put on, but you get used to it.
I stuff my gloves under the hood when we stop for a break. This helps keep them dry and takes care of the icing problem.
As everybody else mentioned, try different ones and go with what's comfortable for you.
M-niner has a good idea...take two pair, one for the hill and one for the ride to and from the hill.