I have slept there a couple of nights with my girlfriend in October 2012.
Our room was really big and had a kitchen + living room with couches and a table, we could manually adjust the heating and last but not least breakfast was A-MA-ZING!
Anything you would like to eat, they have it and tastes great. We're a bit of sissies when it comes to breakfast but we really could not complain with the SI SUITES one.
We were happy with everything, except one thing:
You have to get OUT the building to go the breakfast's building or to the schwaben quellen (depends on where your room is I guess).
Anyway, I would definitely go back there again.