The only negative is that they are a little loud. The first time driving with them I had the top and doors off and was merging onto a highway. As I was driving in the merge lane, I slowed up because I heard another vehicle approaching next to me. When he didn't appear, I looked and no one was there. That's when I noticed that I "heard" myself!
I think they look great. I haven't had them in the mud yet, but they were great in the sand. Based on that they should be just as good in deep snow.