PCM isn't intended for use on electric cars, it is intended for nitro cars because of the battery and interference fail safe features available. If you ever goto a big electric race, you will never see any of the pro's using PCM because it is a little bit slower than PPM or something of that sort, I don't know the exact details.
HRS is a great thing, however unless you're a professional driver who has been racing for 10+ years, I highly doubt you will be able to tell the difference between HRS and PPM while on the track. I use HRS, but I turn the steering speed on my 3PK down to 40%. HRS is very precise and very fast, a beginner or weekend warrior definetly will not be able to use all of HRS' capabilities, I know I can't.
I'm going to be switching back to PPM for my electric cars and i'm going to be switching all of my gas and nitro cars to PCM.