Its been looked over by a guy who previously the foreman for the local VW dealership for years, he works on all my cars so I have faith in what he tells me.
Its going into limp mode everytime I hit 65 - 70 mph, I re-start the car and its fine until I reach that speed again.
Its been checked on vag com and it says its overboosting. Also, its got a pretty comprensive service history and there's no mention of it having had a turbo previously - its currently a few hundered miles off 150,000 now.