Let us not forget that for the majority of users, for the first two iterations of the MMM at least, getting what you paid for meant random fires, dodgy cases, BEC failures...
I've not had a single fault with any of the cheap ESCs I've picked up over the years. I've blown 2 hobbywing 80a escs, one from over amping it in a speed run truck and the other taking a direct hit at a skatepark and cracking the PCB.