I read some advice on a Tech forum this week that advised against upgrades of OS's. He recommended doing a clean install of the OS (not an upgrade) and use a new Hard Drive to install the version, leaving the current intact and out of the machine when trying the new version.

But that seems like an expensive and overcautious approach. Mac, I do like the possibility of using my C and D drives like Bobby wants too. However, I'm still not convinced I should try 7 yet.