I installed these mitts on my road bike and my wife's last week. We rode 5,000 miles in 2014, and decided to go colder this winter. So far we have been down to 35 with the mitts, and this review is based on 72 miles on the saddle. A monkey could install the mitts in five minutes. After reading the reviews (does anyone else start with the one-star reviews?), I bought large. If there was extra-large, I would have bought that. I also bought large for my wife, who takes a woman's medium glove. She says she would not have wanted them any smaller. Before these mitts, I could ride only 9 miles in mid-30's weather without stopping and warming my hands. That was with Pearl Izumi lobster claws and Manzella runner's gloves worn underneath as liners. With the mitts, I use Pearl Izumi Cyclones which are good down to only about 45 without mitts. So far we have been out only down to 35, but I think with the mitts my Cyclones will be good down to 30. The mitts showed me that almost all of my cold-weather finger discomfort was caused by my forward speed. I don't have to worry about my fingers if they are out of the wind. I also considered Arc'teryx Alpha gloves. They were $275/pair, and no guarantee that they would be warmer than my lobster claws. The mitts were a lot cheaper. Pay attention to the types of mitts. I bought for Shimano external cables. Works fine. Before mitts, I put my thumbs through holes in my hoodie, so my hoodie sleeves would tuck into my lobster claws and the wind wouldn't blow up my sleeves. My hoodie is made for that. With the mitts, no way is any wind going up my sleeves. The first mitt-ride, I forgot to put my thumbs in the hoodie-sleeve holes. I learned that I didn't need the sleeve-holes anymore. That's the good news. The reason for only 4 stars is that your hands must stay on the brake hoods. That's not my normal position. In that position, my hands ache. I shake them every few minutes. Still, it's better than freezing fingers. I can ride with my hands between the mitts, on the top bar, but my fingers get cold, and I have to dive back into the mitts to warm up. I could try thicker gloves, but there might not be room in the mitts for the lobster claws. With your hand and the break/shift levers and hoods in there, real estate is precious. Maybe I will get used to the position. I saw a question about whether you can get your hands out of the mitts in an emergency. I doubt that it is a problem. I got used to them right away. Plus you never know in a crash, you might be better off taking the whack on a shoulder with your fingers protected. Could we use a fairing, like a motorcycle? What would it weigh? The rest of the bike is only 20#. And what about wind resistance? With the mitts, look out for wind gusts from the side. The aerodynamics are greatly affected by having that much fabric that high on the bike. Bottom line, this is work in progress, but you can ride pretty darn cold in these mitts. Update: 350 miles later, still no opportunity to try these mitts under 35 degrees. We remove them when the temperature is high 40's or higher; removal is quick and easy. One year later (January 2016): We are riding down to 32 degrees. For cold protection, these mitts still beat any glove I have tried, easily. With the right gloves we could ride a lot colder than 32. Also the mitts show no wear, even though I often remove or remount them. Which is quick and easy to do. Which returns me to the one drawback. I remove them whenever the weather allows, because to use them I must keep my hands on the brake hoods. That position is painful for me. I have to lean too far forward. My hands and elbows ache. The position limits my mileage range. So when the air gets warm enough, the mitts come off. A few days ago the weather was right in the middle, and I was okay for a while with my hands on the bar inside the mitts. I came to a street crossing; a car snuck up on me from the rear to turn across my path, and it was too late to insert my hands in the mitts and pull the brakes. I was dead if the car didn't stop. Also, the mitts significantly increase side-wind resistance. We have not been out in 20 mph straight crosswind, but it doesn't take near that much to make the front wheel squirrely. 1 week later: I should have mentioned that I have the mitts on a road bike with drop bars. Today I noticed that the hands-on-hoods position was more comfortable if I kept my elbows bent. That requires leaning forward, but it helped.
