It's just like running SQL Server on a virtual. Do you have enough resources? If so, yeah, it's fine. If not, no it's not. Actually, same thing as a physical box when it comes down to it. Does it have enough resurces? Then you're good to go.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning