You'll find mixed feedback regarding DP and most tuners to be honest....i'm sure i speak for a fair few club members when i say you would be better going to an engine builder rather than tuner as they will be cheaper for one thing.
If i was you i'd take out my own engine, with the money i save buy a little run around and make sure the job is getting done by the right people at the right price rather than rush into anything you may regret.
I'd also pm Rishi, he has good connections and would be able to offer good impartial advice.