the 7700 is way too many kv for the slash. That overheated quickly and thus gave out quickly. The 5700 is still pretty high for a slash...If you don't gear way down or just do a few sprints at a time it's no wonder that one gave out as well. I'm running a 4600 mamba in my slash, and it still get's pretty warm at 16/86 gearing. As for the brushed motor, it depends on what it was, if it was the stock titan, those suck anyway. Pick up a VXL motor, at 3500kv it has much more torque, you can gear it higher and there will be less heat issues.