Your 1515 should do wonderful with the Monster Max ESC. I would not bother with a combo since you already have the 1515. The castle 2200 is just an inexpensively built Neu. If you need another motor for something else, then the combo might be a good idea.
the only reason i was going for the combo is cos i need a complete set for the lst just want to get the right motor for it
and i use the nue in the revo and i have spoke to a few people say the reason why i may have cooked my esc's is becouse of the motor
please forgive my lack of knowledge on bl set ups still trying to understand it all