Should I consolidate my SQL instances? I'm trying to find an answer to this one with not much luck.

I have an MS DB server with our main databases on it. Over time, someone has installed SharePoint and Microsoft Online (365) services which both created SQL Express instances.

My question is, SHOULD I move the databases off the SQL Express instances on to my main one and uninstall Express - and if so, why?
SQL Express has many disadvantages. If you've already paid for a real license you should use it. You don't have to consolidate everything in one instance, but I prefer not using Express...

See http://msdn.microsoft.com/en-us/library/cc645993%28v=SQL.110%29.aspx

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