I have more trouble with After Effects 5. Some "compatibility settings" got it to work, with QuickTime 7 even, for small projects but large/long ones fail out at render time and I have to go back to Win XP to get things done.
I haven't bought a major app other than A:M since about the year 2000 so in most cases I'm working with software that MAY have been aware of Win 2000 at the most.