When my wife was alive, we looked at the Z3/Z4, but it was too short for tall ppl. I'm only 5'10", but my wife was almost 6'. The S2000 actually had more head room. I also like the looks of the Z3/Z4, they only come in rear wheel drive
Sounds like you've done more research than I have. All I've done is look at the styling of the Z3/4, and I know I like what I see. I haven't sat in one, just looked at a few from time to time whenever I can. I like most of the 2 seat roadsters on the market, but it was the bike or one of those.
I chose the bike.