The Hobbywing is the best performer for your $$ that's for sure. I don't run one, i'm all Tekin, but you can't argue that HW performs great for the $$. These days it's more about if you know how to set up the ESC, and if you know how to transfer what's happening on the track into changes on the ESC, just like suspension tuning.
FWIW one of the guys at the track runs the latest Speed Passion, which is the same as HW, and he is the fastest by a long shot. But he is one of the top drivers in NZ, so you'd expect that.
Buy what you can afford, based on what your favourite colour is, and get out there.