We stayed there a few years back. They were just renovating it, so it should be nice for your stay. I was pleased with the hotel. We've stayed at many of the deluxes on property too. When we did stay there we switched over to DL for the remainder of our stay. Honestly, I almost like Hotel Royal Plaza better. The restaurant downstairs had a great breakfast buffet. The rooms were nice (they had an "island" feel to them) and we weren't in the tower, we overlooked Hotel Plaza Blvd. We were able to walk to DD (they were just expanding it then so now you could spend half a day there if not longer). A tower room should be really neat though.
Honestly we never took the buses to the parks, but I did notice them leaving every 20-30 minutes. I believe that's the schedule. We've stayed at the Grovsner a few times and I would definitely recommend this hotel over that one, that one really needs some renovating, plus the Hotel Royal Plaza is bright and cheery. We spent some time at the pool and thought is was nice also. If we couldn't stay at the S/D or WDW hotels we'd probably stay there again. Have you checked their website for details?