Hi yes...I had my 3.0 petrol cab done there a couple of years ago...only charged me £180...fabulous! Mine's a non turbo petrol so it was quite a subtle improvment but deffo felt it...if yours is the 1.8T or a diesel turbo then you'll feel a lot more extra oomph than i did...i just got about 25hp and about the same torques!
Basically he gives your car the once over for any hidden codes and will probably clear them, then emails your car details (model, VIN, engine type etc) over to a mate who writes the map for your car model. He then receives it back and applies it on to the car, then you'd go out for a test drive for 15mins or so with the laptop plugged in seeing how the engines doing...
Took about 90mins all in...had a great drive home...
Its quite a good business and he does know his stuff in this field...I had high confidence in him...when he did mine he was doing 10-15 cars a week....
Hope this is a help..
Andy