Overheating can be down to running the engine too lean though. Although I bought a Nova cooling head for mine which helped it's restart time a lot after doing a tank.
Mine had the 2.4ghz kit in it which I had no issues with, think I replaced the switch at 1 point. Naturally upgraded the steering servo but used the old steering for the throttle without problems. Never replaced wheels or clutch though in the time I had it went through 2 gallons before I sold.
I wasn't gentle with mine at all, chucked it off cliffs MX bike jumps, car park ramps the lot! I think there's a vid link in my build thread link in my sig.
Sounds like you have been unlucky as mine was a dream to own and they have a huge following in the US.
Body posts were a weak point, I just replaced them with nylon rod so they had a bit more give.