Revos vs BFG AT
Being a former owner of BFG AT I can attest to their off-road worthiness. They will survive some serious rock-crawling, although they are not good for deep mud, they do survive almost any condition trail that you will encounter.
I can also say that these tires suck for on-road performance. The don't handle large volumes of water well at speed (very prone to hydroplaning) and because of the triple sidewall, ride very stiff (like a buckboard). Because of the tread blocks, they do well in snow and dry pavement, but are noisy on the street. Also due to the sidewall construction they are heavy (I believe these are 3-5 pounds heavier than the same size Revo).
If you want good street and light offroad (sand, dirt paths, no rock crawling) performance, stick with the Revos. I you want good off-road performance (sand, rocks, branches, no deep mud), and don't mind a little more noise on the street go for the BFG AT's. If you want serious off road performance go for the BFG MT's (go through anything, more street noise).
Get a tire for what you will be using it for most of the time.