Ever since I decided to reinstall test/development-environment with a dedicated SQL-server I have been having trouble. At first the MPs wouldn't even import during Service Manager installation, and eventually it would timeout and rollback the entire installation. Then I figured out that if I set the default database size to somewhat more than 2000 mb (I think anywhere from 3500-5000 did the trick) the MP importing suddenly worked, although very slow (anywhere between 1 minute to several minutes to import a single MP or MPB). After installation (takes several hours) it would take up to 30 seconds to create an empty MP in the console. More details described here: Technet.
Since then I had reinstalled my entire server, put it into a box due to me moving, and I have finally gotten around to taking it out of the box and setting it up. And I figured out what the problem was!
Setting the maximum (and minimum) memory allowed for a SQL instance did the trick! The SQL-server was simply starving the OS for memory, and I guess the increased DB-size somehow gave it a (slow) disk-buffer, allowing it to import MPs, but at a very reduced speed.
If you have a limited setup this is something you want to do before even starting the installation. I suggest Googling/Binging/(Insert your favorite search engine and add 'ing' to the name) best practices and such. Then go ahead with installing your favorite System Center component ;)
Anyways, hope for and expect more frequent updates from now on.
Duly noted!
SvarSlet