2008 Z1000 compared to a 2003/04?

Hi,
Ive been humming and Haaaaing over a change of bike for sometime and now have decided that id really like to go for a 2003-05 Z1000. Id go and 08 but if I get a new bike my wife would have to get a new one too...! Im in adelaide and there are a few I can look at for sale, but my question is - is there much, if any, difference between the years in seating position and height etc or is the frame basically unchanged? Its just I may have to go fr a test ride on a new demo to get the "feel' of a Z so I have something to compare the feel with in case i find myself testing a dodgey one!
Also when it comes to after market exhausts and single sided systems should anything I consider have a power commander or is the issue of leaning off not a huge problem on this bike?
Any ideas would be much appreciated.
Ive been humming and Haaaaing over a change of bike for sometime and now have decided that id really like to go for a 2003-05 Z1000. Id go and 08 but if I get a new bike my wife would have to get a new one too...! Im in adelaide and there are a few I can look at for sale, but my question is - is there much, if any, difference between the years in seating position and height etc or is the frame basically unchanged? Its just I may have to go fr a test ride on a new demo to get the "feel' of a Z so I have something to compare the feel with in case i find myself testing a dodgey one!
Also when it comes to after market exhausts and single sided systems should anything I consider have a power commander or is the issue of leaning off not a huge problem on this bike?
Any ideas would be much appreciated.