It's mighty irritating that the Roo views command alternatives available when pressing Ctrl+Space bar after writing "--", for instance, still are obscured in STS 2.7.1 by the popup help window. Why can't it popup out of the way without obscuring the very command alternatives themselves? See attached screen dump for illustration.
This is my experience back since several versions of STS, both on OS X 10.5.8 and now on Windows 7.
I will file a bug report unless someone convinces me this is easily avoided.