LRP make pretty good ESC's, so I would worry about running a motor close to the ESC limit. The key really is about run-time. If you are planning to throw in pack after pack for an hour of running, ANY motor will get damn hot. The main issue with heat, is that it results in lower power, and your brushes will wear faster.
Mod motors are designed for racing. Races are generally 5 or 6 minutes, then the motor has time to cool down. Running low-turn mod full bore for 20 minutes in the carpark is great fun, but it will shorten the life of the motors a LOT, especially if you can't skim the comm often.
If you can afford it, I think brushless is great stuff. I don't have one, but that's purely a cost issue. Very little maintenance, and you can gear them up a lot more than brushed so you will have higher top speeds (which is what i'm guessing you are going for). Perfect for all bashers