Every tire has it's place...There' a reason you see alot of BFGs (along with other hard compound tires) on street rigs, and you see MTRs on alot of rigs that get wheeled. I take it you arent talking about Krawlers(KX), but the reg MT/KMs. If you want long lasting street wear, get the BFGs(MTs) If you want good tread wear AND trail performance, get MTR. If you compare the sidewalls of the 2 tires, unmounted, it's scary how thin the BFG MTs are.
The few trail rigs I've seen run BFG MTs, just wont hook up where other tires do, and they end up leaving a pile of rubber shavings and going nowhere. I have ripped a couple of MTRs-but I was slamming them into sharp rocks and that happens. I have seen BFG MTs rip on things that just shouldnt be an issue. If your going to go BFG, go with Krawlers-sweet tire there(if you can afford em) There's a reason there are so many trail rigs running MTRs, for the perf, and price, you just cant beat them.