PGT9
I did the same as you - but ran the turbo at far lower boost while waiting for Karl to map my car.
I have a wide band AFR in the car so I could at least see what the fueling was up to.
HOWEVER - I personally would not recommend it - and suggest either hanging on for Stu, or if you are desperate to get running then ring other tuners if needs be. Personally I used Karl as he has done good work for my brother, loads on here use him, and he had a slightly shorter waiting list.
Having now met the bloke, and since driven the car, the money spent was well worth it. T38's transform the car.... but don't melt your engine --- that's never a good plan!
Si