Well Ive had it all apart and cleaned so I dont think its anything to do with the calipers. The squeal occurs on both front brakes and if I turn the wheel while driving say 20mph, the squeal goes quiet one side, and louder the other. Has to be something with a high point as there is a time blip between each squeak/squeal. When I had a wheel off and tried rotating the disc, you could here a distinctive rubbing noise like there was a tiny bit of friction. Hmm, well the garage is going to test drive it and find out. Does give me an excuse to play ACDC really loudly though :P!!!!