We dove with them in June 2005 and found the operation to be very well-run and professional. Boats were clean, comfortable and well-maintained and the dive op was very flexible and accomodating. Because they are so close to Bunaken (just a 10-15 minute boat ride), they usually come back to the dock between dives so you can do any combination of dives during the day. Also, they do trips to Poopo, Bangka, the northern islands in Bunaken Nat'l Park and the daytrip to Lembeh pretty much upon request. Simone (the owner/mgr) is usually very responsive so if you haven't heard from her, just keep trying, or try to contact her through the hotel.
I can't comment on the liveaboard since we didn't take it, but we loved the Santika hotel where they are located and are looking forward to going back next year.