Positives - The bus is cheap and easy (albiet not as cheap as the trains, but a bit less confusing). It takes you right to the doorstep of the attractions which is very useful for those places out of the centre or not next to train stops (bird park, palace, national museum) so worth doing for these places.

Negatives - Rush hour in KL is between 4-7pm and the city grinds to a halt, particularly if there is a thunderstorm. We waited over an hour for a bus in china town (stop 8) rather than 20-30mins and abandoned the trip at stop 11 (KL Sentral) to get on the train system.
Also the bus goes one way on a loop and can take well over an hour so plan carefully.

I would use the bus again but use early in the day (it is quicker due to traffic) and use to get to those more distance tourist attractions. Its also a good way of getting your bearings in the city.

Very satisfied. It covers a large area of KL.
Ticket price is very affordable.
Best way to discover KL in a short time.

Firstly, I need to mention how great the staff were. We used the bus a several times over a couple days and we were very impressed with how polite and nice the staff were - great work! We did the full loop a couple of times and there is a couple of points where you go through the same area. Surely you could have a full loop without doubling up on areas. The commentary does not always line up with the destination. And you need to provide more info when stopping at a destination e.g. The palace - we didn't know if you can enter or not, also ticket prices for some places (tower). Otherwise you have to leave the bus to find out for yourself and then wait for another bus.

Buses were clean and comfortable and as I said - great team of staff!