There are several posts on the Klim and the No Fog if you do a search. In my opinion, they are a bit apples and oranges. If you want to buy only one that will work in very cold conditions but isn't all that comfortable and a hassle to put on and take off, go with the No Fog. If you want something that is more comfortable but might leave you having to stop occassionally for a wind break on long grade ride at 10 below, go with the Klim. I've got both and carry the No Fog in my tank bag for those extremely cold situations. Otherwise, I prefer the Klim.