Thanks to both!
Definitely noticed a change around highway speeds! You are not going to notice anything off the line from this though, as noted before. Its great for stepping on the gas to avoid something or get around a slow driver in the left lane :P I punched it today and it really takes off. Before the install, I always felt like I could sit behind a car, floor it for a second or two, and then start to merge to pass them. However, now, I feel if I do this I will ram them in the rear! I mean I may be slightly exaggerating but I like the improvement! However, my opinions are slightly biased. The real test is to ask those that have already installed (v1-v3) and get their thoughts.
As for economy, lol don't ask me. If it helps, my economy hasn't changed and lets just say, i've been putting my car though a testing phase for the past few weeks :P So I image a slight increase in MPG is plausible. However, it really depends on the driver in all honesty.
Only way to find out for yourself is to throw one in there ;)