While Sterling does have a larger and more modern ship than SunCruz does, that is the only positive thing that we can say for them.
Our first casino-cruise experience was on Sterling. We called ahead of time to ask about wheelchair accessibility, and were assured that there would be no problems whatsoever, and that IF we required any assistance, the ship's staff would be more than glad to help.
Our experience was exactly the opposite. The ship was not very accessible at all, and the one & only time we did ask for any help, the crew member was downright rude to us, telling us he did not have time to help (all we needed was help through a door that had a barrier on the bottom - it would have taken about 30 seconds of his time at most - a fellow passenger ended up assisting us - the crew member was just standing off to the side & simply stood there watching - he wasn't even doing anything)
The "elevator" that was pointed out to us for a wheelchair to get from one deck to another was a joke - I think it was some sort of dumbwaiter-type service elevator. My husband had to literally pull his legs up folded into his lap, because the door would not close if he left his legs down in a normal sitting position - the door caught on his feet!
Food was mostly awful. There were some delicious muffins & cookies, but the 'sandwiches' they offered tasted like cardboard, and other choices were bad too.
I don't understand what the problem was when we took this cruise - even while in the casino, we tried to get drinks & the waitress outright ignored us, even though she was serving the customers on either side of us!! Perhaps they assume that a person in a wheelchair MUST be a poverty-stricken welfare case, and that we were only there for "free food & drinks" - I don't know. All I do know is that we were treated rudely when they did speak to us, and ignored altogether half the time.
Nothing could convince us to ever set foot on Sterling again. We were quite hesitant to even try the cruise experience again, but did give SunCruz a shot & it was a world of difference! Maybe 'regular' people are treated well on Sterling, but we had a miserable time & were treated as if we weren't worth speaking to. SunCruz treated us courteously & pleasantly, just like any other customer.