well i have had my z3 1.9 8v for a year know and although most of the time it is a good car its just not got what i like in a car power, iam not a speed freak but do like power on tap when i want it, have looked at a few 2.2 but fell that i have a rely nice car but fro the lack of power and could be disappointed in the condition of other cars , so the way to go is change to a z4 iam going to look at a 2.5 se looks different from the standard z4, try it and see if it is worth the change