I had about 1&1/2 weeks there during December. Booked into a Prestige Room as I needed a big desk to work at. My Platinum status already gave me lounge access so there was no upgrade as I was told the upgrade was the same room plus lounge access. The only downside was on the day before check-out the AC unit dripped water through the ceiling, but they moved me within an hour to an identical room on another floor. I liked the lounge, it's also where you can check-in away from the lobby check-in: very quiet for early breakfast and nice for evening food - some of the staff were very nice to chat with and constantly there to get drinks/food/information. Also, I used the gym daily but not the pool, it's a reasonable gym with a large floor area non-machine exercises but not much space/benches for weights.
Next door is a Banyan Tree hotel, you go in there to access the lift for a walkway into the shopping mall. Also, it's a nearby walk from Raja Chalan monorail if travelling from/to KLIA via the train, as I did with my cabin baggage.

The previous year I stayed at the nearly Novotel. The Pullman is much better.

Being KL, both were great value for money and I'd use the Pullman again next time.