i saw a 5b for the first time at my LHS a few weeks ago... i actually had dreams about it, i wanted it so bad! big, and super tough! then i started to think about the cost of a brushless system to push that thing around, and had second thoughts...
did you see the video of HPI running the 5b across 100 miles in baja country? it can really take a beating!
edit: here it is.