there are lots of differences.
power consumption is a main diff
what is your application?
i started with a MMM 2200 in my slash 4wd then found that the esc was best on 4s so i sold the esc and got a MMP which runs much better on 2s and that combo is great for my slash. also the MMP has the ability to run sensored motors. but i would have liked to have the 2650 motor, a little more speed.