The carpark was very close to T5, the transfer was very quick and we didn't have to wait long for the shuttle.Plenty of parking places to choose from. The only down side was the queue at 06.15 on a Thursday morning for the Long stay carpark which overlaped the entrance and delayed the entry to the Business Carpark.Also the printed instructions for exiting the carpark were a bit misleading.Instead of having to show your proof of resevation for exit you only needed to use the entry ticket from the barrier in the exit barrier.
Bus did seem to wait a long time in the car park for more passengers. good for the passengers who had just arrived but not so good if you have to sit on the bus waiting.