Very warm, Very tough
I love these gloves and find them quite warm. They come in two "parts": a Gortex shell and a polyfill liner (in red color). The combination is excellent. I live in Minnesota and bike commute with them regularly in -2 degrees F. Eight miles in my hands are sweating! This is remarkable because years ago I suffered severe frost bite on my left ring finger and since then the digit has always been susceptible to the cold. No problem in these gloves. I find the liners dry fast and the durability of the gloves to be excellent (the outer fabric is tough!). The dexterity is good but not great. But I've never found super warm gloves that had superb dexterity. In my view, there's always a trade-off with mittens: these gloves are almost as warm as alpine mitts but obviously have superior dexterity. I'll take the trade for most of my needs. Finally, I've got big hands and find the XL to be a perfect fit.

Great Fit
Bought the gloves for high altitude mountaineering. I haven't used them in that arena yet, but I live in Michigan and worn them and found them to be very warm and fits great. I will update this review when I visit the high altitudes.

Worth it if you have cold hands
Appearance wise, these gloves appear to be very quality made gloves. The materials are quality and the primaloft insulation is second to non when it comes to synthetic insulation. I have a large hand and I ordered the largest available glove (XL), and I feel it was a little tight on my hand (at first), slightly limiting my dexterity when I first got the gloves. After using them for a while, they "broke" in allowing better range of motion for my big hands. I wish the palm was a leather like on the Alti Mitt's I have, but they used a synthetic rubber material. I find the gloves for general high activity use are too warm with the primaloft liner in them (at lower altitudes). The gloves are lightly insulated even without the liner and for high activity, these gloves work well with no liner, or just a thin glove liner. Obviously for high altitude or extreme cold, I recommend the liners. The top of the glove in the area of the knuckles has a stretch fabric which is nice and helps keep the movement of your hand natural. The gore tex lining works well and has always kept my hand dry from the outside. For those of you unfamiliar with the Outdoor Research warranty, it is absolutely amazing. You will never need to buy another pair of gloves again. I have not used the warranty on these gloves, but I have dealt with it in the past on gaiters.

Not warm enough for me
After trying every kind of glove and liner out there to keep my hands warm the Outdoor Research Men's Alti Glove was recommended to me. We ride ATVs in the mountains of Tennessee in the winter time and I have had the worst time trying to keep my hands warm. The glove was well made and waterproof and I loved the removal liner. However, my finger tips were freezing cold within just a couple miles on the trails. Additionally, even the men's small was too big for my hands and they did not make a women's alti glove. The customer service people have been excellent to work with and I am exchanging this glove to try the Women's Alti Mitt to see if this will give my poor frozen fingers the warmth they need. This is a good glove and obviously well made, it just wasn't warm enough for my cold natured fingers.