Threads like this are pointless - you're talking about three completely different cars, the one you pick will be the one YOU like best after much consideration and a few test drives.
The Porsche is the "race car" of the group, the other two are beautiful cruisers, but all have their strengths and weaknesses - characteristics only the OP can determine for himself.
So, in three years, or whatever, take some time and explore.
2000 Mercedes Benz E320 (daily driver)
2007 Infiniti M35x (wife's)
2006 330 cic ZHP 6sp (current)
2005 Z4 3.0 sp nav x-leather (retired)
2000 323i PP (best car, ever - retired)