In reply to Ben.o.neill:
Yes, and avoid the sun! I was also there a few years ago and can echo the same. A good crag for a few days max.
We stayed in a hostel in the center of KL, and actually the owner of the hostel turned out to be a climber. He gave us a lift to the crag and we climbed together and met some of his friends. I recall there being a small kiosk nearby that rented gear, but can't remember near which wall. Car is definitely the easiest way to get there, but i certainly wouldn't stay near the crag - there isn't much else there and its better being near the centre of KL, the food-stands, the life etc.
The temple itself is quite amazing. Do check it out and watch for the monkeys
Depending on your travel plans, if you make it to any other areas in Malaysia I can also give you a few tips on climbing areas, as we spent a month exploring and searching them out (e.g. Tioman Island or on Sarawak, Borneo)