I've got RaceChip on my 320d N47 engine. I don't think it achieves the sort of figures they mention on their site, however I can certainly notice the difference though and the car feels much more 'alive' with plenty of poke.
I've had it for over a year. The first one they sent me, after 2months the car went into limp mode, after taking it off, it was fine again. I called their UK support and asked me to send it back to them and they sent me a new one. Not had any issues since though
