I have a pair of the Specialized Defroster boots because Specialized shoes/boots fit me well. They are a bit heavy, but they are waterproof and they have kept my feet warm in temps of 0 and lower. I suffer from Reynaud's and while my hands are usually the worst, my feet can often get really cold and hurt quite a bit. The Defroster boot has prevented that. Paired with a wool sock, my feet actually are almost to the point of being too warm if that is possible. I have field tested these this past winter in a blizzard. I walked my fat bike home on a commute the last mile through snow that was easily a foot deep. My feet were very warm and dry.

Being a size 13 or 48 EU, covers and booties simply are not made big enough at least in my experience. I tried the Pearl Izumi velcro overwraps and those are so hard to get on and they don't really work that well. As for the closure, as long as it works, I don't care what it is. The BOA system on these has been flawless so far *knock on wood*. The price, not so cheap.

One thing I have noticed with these boots is that you may have to adjust your saddle height up. They add a bit of height to your shoe with the sole/insole and I found myself feeling "short" while riding. Quick adjustment and everything was back to normal.