Very stable for me as well - though you'll hear some horror stories from some people here. Depends on your computer, I suppose. If it means anything, I had a full copy of an earlier version that came in 3D World Magazine (version 2 or 3 - can't remember) and it crashed every time I even tried to start it up - uninstalled it without ever even getting a chance to use it. Heard great things about 5 and decided to take a gamble - been thrilled with it ever since!

ILM is saying great things, but also keep in mind their computers aren't purchased at your local consumer stores - there's a good shot they're running on SGI workstations, so it's kinda apples/oranges I'm sure. They also have tech people (not your standard IT types - this is for a production environment) to keep their systems as glitch-free as possible.