I'm currently running a set of 34/10.5/r15 LTBs on my truck. I run them in mud, since that is all I have for terrain around here. They work great offroad, tons of tracton. Pull better than BFG muds/radial TSL swampers/mud kings/thornbirds that I have run in the past.
Did I just admit to having thornbirds? <img src="/forums/images/graemlins/zombie.gif" alt="" />

They ride ok on the street under 55mph, anything above that and it's like riding in a paint mixer. I had 16/35/r15 boggers unbalanced on a 15x14 steel wheel and they rode better than the balanced LTBs. The boggers did pull harder, but I couldn't turn them as easy in the muck so the LTB's actually get me further.