This is rewriting the ECU sotware, it's impossible to detect!
And it's reversible. So no problems with the warranty!
And these values are conservative! There are Ibizas 130bhp with >220BHP here in Portugal! As well as Megane DCi100 with 150BHP.
When the WTCC was here in boavista the BMW engineers were very impressed by vilauto's 330D.
And... it's not only a power increasement! You also get better millage (on normal driving)!