I've only ever run a smart diff in the center of the truggy and it came out very very quickly. I absolutely hated it! It made the truck feel extremely weird to me. It took away all smoothness on the throttle. Almost like it wasn't locking and unlocking fast enough. I am a pretty smooth driver. I like to roll on and off of the throttle. With the SD it seemed one step behind me. It wouldn't lock quick enough when I rolled on and wouldn't unlock quick enough when I rolled off. For someone who drives very aggressively/ with a lot of on/off of the throttle it may be the best thing since sliced bread, but for me it was the worst my truck has ever felt. Didn't take long for the standard 10K diff to go back in. 7/10/3 and that's about it. Pretty much what I run exclusively in the truggy.