It's bloody awesome. I have done a comparison with fuel figures from before and after.
Before the tuneup, our best was around 15.7ltrs per 100kmh
Since the tuneup was done, 1st week after tuneup was 14.6ltrs per 100kmh
I have done a 2nd test after the tuneup and we managed to get it down to 13.3ltrs per 100kmh
I could probably get it down even further but I have a lead foot.
I'm our opinion it was well worth the money