coming from an rsx (type-s i assume?), you
will notice a difference in the gear box. the rsx is much smoother and easier to shift, but i have no complaints after a month of owning my z. handling and road feel are about the same or better in the z than the rsx. although, im still in the break in period, so i haven't taken the z anywhere near the limits yet.
i can't compare to the rx-8 since ive never driven one. i hate how they look, but that's just my opinion.