In theory, it should be fine from a technical standpoint. But I vaguely remember having problems with multiple organizations in previous releases, though I don't even remember any specific instances.
However, I personally don't agree with doing any "development and testing" on a production system, other than maybe load testing or something similar. In my opinion, production is reserved for "this is what works."
This answer probably didn't help, but at least gave you something to think about.
Good luck
PS, you can clone a production system and be up and running relatively easily via use of the hosts file and a file system copy, assuming you don't mind keeping the same host name on the new machine. Vaulting may add a bit more complexity. Just be sure you have all your hostnames and aliases covered before you fire up the new instance. You don't want to hit your production DB from this system.
