I used dolphin for the company hack as its up the road from work...
They job was good, they even wiped all the dust out of the door sills after i went off road... They also put tyre shine on the spare wheel which is up under the rear of the car where no one will see it...
But ill try and use this Mt Gravett one some time, its just i dont get over that way at all with out making a special trip...