I was wondering what people have found to be a mitt that will keep their hands warm and durable enough that it will not fall apart or start to shred easily. Thanks.

Or waterproof outer shells?

I recently purchased a pair of 3-in-1 from REI and used them this past weekend up in the Dolly Sods Wilderness in West Virginia. Temps ranged from 30 down to the low teens with light snow, some wind. I was carrying about 30 lbs, and hiking was fairly easy. I loved these gloves. The outer is mitten, waterproof and windproof with Thinsulate...not sure the rating...and the inner glove is a glove with great grips on the palm and fingers. The gloves worked well to do chores around camp, using my poles when my hands were hot, and are also insulated.

A friend came unprepared and used the outer mitt to warm her hands. The palm on the mitt is leather, but I've already thrown the things in the washer and hung to dry...look as good as new.

They are easy to tighten by pulling one side of the cuff string and ubtighten by pulling the other side of the cuff string. I think it's for snowboarders because it has a nose wipe and goggle cleaner but hey, they get wet and cold, too!

Do these folks have their ears to the ground or what:::
http://www.backpackinglight.com/cgi-bin/backpackinglight/bmw_featherlite_vapor_mitts.html

I saw them but as nice as they are, I didn't feel like taking out a small loan. Plus, for me, I like the idea of being able to use the liner glove that came with them or use my own.

Sierra Trading Post has a couple mitts. These look a bit heavy but warm! Link
Or these Mitts should be somewhat durable because snowboarders drag their hands.

What is the intended activity? I got some OR PacLite mitts that are OK, but do condense a bit on the rubberized palm.
Andy Kirkpatrick has a bunch to say about mostly gloves:
Psychovertical He likes powerstretch and shield.

I want them. I'm not sure I'm prepared to spend that kind of money on mitts though...