I like them, but I can't compare it to any other crawler motor. Mine tops out at around 8mph I'd say :lol: When I go on trail crawls, it keeps pace with me walking at about 70% throttle. Full speed is about jogging, I'm sure I could out run it

If you want torque and speed, probably look at one of those Cobalt motors.. they are $80 though.
Mamba might work, but two things I'd be worried about. 1 - Cogging. You'll be at low throttle a lot, if you get any cogging it will burn your esc in no time. 2 - Low end throttle control. You could program it in Castlelink to have a real low throttle curve from say 0-25%, but it would take some adjusting. You need to have a smooth curve at low throttle to work over some rocks.