I installed my Sport Tuner module over the weekend. Due to some bad weather and heavier than normal traffic, I have not had many opportunities to go WOT. The problem with this car is that in second gear, you go 20-50 in just a couple of seconds. Same thing in third gear, going say 30-75 merging onto the highway. I quickly either run out of space, or far exceed the legal limit, so evaluating the improvement is difficult. There is definitely some increased shove at full throttle above 2,500 RPM. I haven't been able to evaluate performance past 5,000, where the stock boost quickly drops off. That is where I am hoping to feel the gains. I am running the unit in the as-shipped +3 psi mode.
I definitely feel this module is worth the $136 free shipping/no sales tax I paid for it. I wouldn't pay $299 when a JB1 with cable can be had for just a little more. I think Dinan would have sold a few units at $199, but $299 is not competitive with JB1 (or JB4). If you can get one under $200, I say go for it.