I'm playing with my settings on the DTUK red power box, it came on setting 7 and wow what an amazing difference. I turned up to 9 and not much difference than 7. I then went to B and it flew up to just under 140mph no problem unbelievable gains! I tried setting F and it lost power compared to other settings (still no warning light or excess smoke though). anyway after phoning dtuk they advised 9 or A the most common. so I'm now on setting A which beats 9 for sure but I'm debating whether A or B is the best as I can't tell? Any one else tried these on a 1.9 Sri CDTI?