xcode 4 crashing Lion

I'm pretty sure everyone who has ever used Xcode on Lion knows how unstable it is and how often it crashes. I had the same problem with my MBP and now MBA on and off - sometimes it doesn't crash, sometimes it does :s

So how have people made it stable (mine is still annoyingly unstable)?

The CPU speeds up to 300%, 90C and fans roar at 6500rpm when I have to force quit...

Turning off live code view improved it (for a while) but now it's gone back to its previous state of annoyance. Any suggestions?

 

Update:

I tried completely uninstalling Xcode then re-installing (latest public/appstore version) and still no success...

I then uninstalled it all again and installed the 4.2 beta 7 - BIG improvements, i'm just gutted I've had to put up with the problems for so long whilst I was developing and update for the appstore - now i can move to the stable beta version and actually work on the big project I was trying to work on!!