Based on the review that Jang @ URC did a little while back, the Leopard ( and Tacon ) motor has similar power to the castle 2200kv motor, similar temps, but a bit less torque in the mid-range. If you are just bashing and not hammering it like a loony, then it should be fine I imagine, no great loss if it isn't given the price. I would favour a slightly larger motor though myself given how heavy your truck will end up:
http://cgi.ebay.com/Leopard-4082-bru...item2566599dfb 4082 2200kv $110
http://cgi.ebay.com/Leopard-4282-200...item3a685f55cc 4282 2000kv $110
http://cgi.ebay.com/New-Leopard-LB-4...item3cba982956 4274 2000kv $90
http://cgi.ebay.com/Sale-RC-Leopard-...item415bf568ed 4274 2000kv $84
just type in 'leopard motor' and search though them all ( price high to low )- there are loads of places selling the same and similar Leopards, larger too, for the same or less money. They will all be covered by paypal so no worries about getting screwed over.
Also, what cell count / voltage are you planning on running? It might pay to go for a lower kv motor, like 1600-1800kv for 5-6s lipo, unless you plan on doing speed runs or lots of high speed on-road driving..