Motor/ESC questions

[BrianG]

I was planning on a 9xl, but am now leaning towards 10xl. I'm using the stock Revo tranny so I have a decent amount of choices for spur/pinion combos. I plan on racing so I don't want any chance of things overheating from stress (assuming gearing is correct of course). I too think the Quark 80 will handle it, but figured it's bigger brother would heat up less and not be as stressed so it will stay cooler longer. I don't want to use a fan either. However, I read somewhere that it is advisable to use an ESC that somewhat matches the motor - something about the current feedback from the motor being more accurate (read: better control) if the max amount of current the motor will pull is roughly equal to the ESC rating. Maybe the quark will let me add a little larger heatsink; but I can't find some decent 360* views to be sure.