I stayed here on my last visit to LV, and it's a great hotel for the location. It's right on the Strip and just a short walk away from Bellagio, Caesar's Palace and Paris.
When I visited Bally's it was just before the summer and they hadn't reopened their pool for the season yet, so they gave us access to Paris' pool instead and I wasn't very impressed, and happy I didn't pay Paris' price tag for a night since I was seriously considering staying there. The pool was in a pretty sad shape and paint was peeling in spots.
The service at Bally's is pretty crappy. There is no other way of putting it. I hope they fix that up, and I'd totally avoid buying anything from their snack bar since the prices are astronomical. (No surprises here, obviously, but I think it's a much better idea to buy snacks from the many drugstores down the strip instead.)
On my next visit, I'm going to rent a car and choose to stay in one of the newer, nicer resorts just off the strip.