I dont know anything about the KO system you are looking at, so I will not be much help there.
But the Hobbywing Power systems work great. Get the 150A version though, the 80A has been known to run a bit hot in 1/8th scale apps. Check out the Turnigy Systems as well, they are simply re-labled HW components with comparable prices. The new Turnigy 150A ESC has sensored capabilities as well. Do your homework and make sure you get what you want and you will be much happier in the long run.