As far from JBS as possible !
Yes they work and do make a difference as they speed up the time delay between pushing the peddle and when the ECU re-acts, fact. Wheather it`s worth the money is everyones own personal opinion and yes i did own and test one for a tuning company.
06 Audi 2.0 PD140 Sport TDI Quattro S-LINE.
Old engine 330 bhp @ flywheel 263 bhp @ wheel 490 lb torque.
Audidriver write up HERE
Now stripped and playing with an uprated Cryo treated engine fitted with bigger turbo,water/methanol,uprated injectors etc etc.Wanting 400 bhp and 500 lb torque.
Other car 500+ bhp MK4 Golf R32 turbo