Hey Harveystern...
Picture quality is not that bad. I personally think that the DIGITAL pq for Adelphia is BETTER than DISH and DIRECTV. The HD pq is ok. I think the HD pq in the DISCOVERY and HDNET is MUCH better than the premium channels...if that makes sense. Also, for the locals, they really do look very good. The only problem is that channel 10 tends to bounce a bit sometimes. Maybe it's the channel because I also have an ota and the same thing happens with the ota as Adelphia. I would say Adelphia offer MORE than DISH and DIRECTV just for the simple fact that you really don't have to dish out alot of $$$ for an HD DVR ....AND no long term contract. I had BOTH DISH and DIRECTV and their pq was about the same(I had BOTH Directv and Dish at the same time about 2 years ago). I have been pleasantly surprised by their good service. Of course I was spoiled by VOOM, but until FiOS gets here, I will stick with Adelphia. As far as switch, that is a tough decision for you. I mean supposedly COMCAST comes aboard in late March/early April from what I have been told, and only GOD knows what that will bring. So IF I WERE YOU...and you are still determined to switch, I would wait until AFTER the switch to COMCAST by Adelphia before I would switch over to cable.
Damn I miss VOOM! FiOS, please hurry!!!! Good luck!