Well, Windows 7 is pretty stable, as everyone's already said. Fast.
Only gripe I have is that MAX 5 doesn't work at all on Windows 7 and OP is sluggish on the D2, and sometimes, and this is personal experience, sometimes it can't connect to the access server, with the error of a firewall blocking my connection, when there was no firewall at all.
Other than that, I've had pretty good experiences.
Oh, and the best part, I loaded a DVD into the computer, and WMP12 played it without any problems or delays. I was surprised to say the least. Also, I found out Office 2000 works on Windows 7 without problems also.
If there were SFC plugins for MAX 9, and OP could be made to work with Windows 7 flawlessly, I'd actually considered upgrading to Windows 7.