well, again; i just want to thank everyone for their input (I saw that someone else asked the same question as I); I'm thinking what I'll probably do is keep my G for AT LEAST another 2years and then see what happens. With gas prices shooting through the roof that last couple of weeks; I'm thinking a paid off car will help with the increase cost of fuel.
Anyway; I think I'll also use this time to do some minor upgrades such as a Z-tube, mrev2 along with a 5/16 spacer. I'll definitely be lurking on the forum; that's for sure since I'm becoming a big fan of Nissan and Infiniti in general.
@former G owners
Hope you don't mind the constant questions about how the Z compares to the G and all. Umm...one question comes to mind real quick; seems everyone talks of the G 'low-end torque'; is that to say that to really feel the Z kick in etc; you have to keep the revs high? Also, one of the things that I really love about the G is even though it's a coupe; it's bigger than most cars on the inside (in particular my old mustang); how does the Z compare to the old one when it comes to space - take into consideration I'm a pretty big guy (6ft 235lb)