I stayed here for a 4 day trip to Vegas. On the plus side, this place has a great location in the middle of the strip. They have also renovated the north tower so the rooms over there are decent for the rate, although cleanliness is questionable given that we found some stains on our sheets (!)
A major negative is the overwhelming stench of cigarette smoke that overpowers your senses as soon as you step into the lobby. The casino at this hotel must have the worst ventilation system because I did not encounter this issue at any of the other major hotels on the strip despite there being a similar number of smokers present.
Also, none of the moving belts were ever functioning.
The water here is heavy chlorinated and disgusting. Do not drink!
The pool is also very mediocre and atmosphere slightly creepy. We ended up visiting a friend at another hotel and had a much better time lounging by that pool.
I did not bother with any of the shows or restaurants here since there were much better options elsewhere.
Overall, Bally's is a decent place to sleep on a budget but that is about it.