i have a z-tube on me g35 sedan. i've read all the posts about each but i don't really remember one seeing one comparing the both of them (popcharger vs. stillen). i was wondering if any of you would have any input on this. i know that people like the popcharger as well as the stillen but there are no dynos that prove stillens gains, only the popcharger. so, i'm not sure .. . any ideas guys/girls? thanks