Donald - Jeremy (WR142LL) had the first remap that Williams did on the Sigma ECU and seems to be very happy with it. Jays also did the TB on his 4/4 Sport but I think you will find he said it wasn't worth it as it made it less manageable lower down & constantly had to be revved hard. I think he thought that going for the 4.1.1 axle would have been better money spent but perhaps he can confirm.
