A little info based on a standard VY Commodore with the installation of PowerchipGold 98 from PowerChip Australia (the most renowned in Australia):
Have you got the standard VY commodore or like an SS or something?? In the standard VY your car produces 171kW at the flywheel but when you have a PowerchipGold 98 installed it will increase the engine power to around 186kW, so a substantial gain...Your torque ratingts will also increase from 375Nm to around 401Nm...
It delivers faster, smoother acceleration and with the power/torque increase it obviously results in faster acceleration and this goes for standing start acceleration as well as through the gears...It really gets the most out of your cars potential, those bits that are hidden and un-noticed...You will notice a great difference in all aspects of driving (I have one fitted myself)...Its very recommended that you use a higher grade of fuel (all the time -- but especially with PowerChip)...You obviously know how expensive it is to modify cars these days, but the PowerChip would be the most cost effective option...Break it down like this: COST= $690, kW Gain= 15kW, Price/kW= $46...To be entirely honest, i dont know how to explain exactly how it does what it does but I can tell you what you achieve, I have fitted one in my VY and im stoked, faster in every aspect and slightly better fuel economy also, pretty happy with that :-D
I hope this helps at least a little matey