I pretty much only use my cars at the track, but I have Spektrum and have never had a single issue with glitching. I've had Spektrum, Airtronics, and KO Propo radios all with Spektrum systems in them. I don't even put my receiver antennas outside the bodies of my cars.

I wonder if you friends problems are caused by the mounting locations of the electronics, low batteries, etc.

As far as actually picking a radio system, the feel of it in your hands is more important than just about anything else. That's why I've gone through so many radios. Go to you LHS and find one you really like the feel of. After you find the one you like the best, you can always look for a used one if it's outside your price range.

Also, I'm partial to the Helios because I personally like the feel of it. But I'm sure the MX3-FHSS would suit your needs fine. You also might check out the Futaba 3PM 2.4 GHz if your looking for a 2.4 that's not the Spektrum brand.