Ive been on two coach trips recently and looked up the hotels on trip advisor. Neither had good reviews, but they were both good for the price we paid. One of the hotel reviews was so bad I was seriously worried, but we had already booked. Others on the coach had also read them, so it wasnt just me. It was actually ok. The food wasnt great but we really enjoyed the holiday overall.
The other hotel had so so reviews, but was actualy very nice, and the food, the staff and entertainment were really good. Rooms were just basic.
Neither were the Ritz, but we didnt pay Ritz prices.
Sorry Ive never been to southhampton, so dont know of their hotels, but I didnt find the reviews on the trip adviser website very helpful.
Depends on the price you are paying, and your expectations.