Not Happy 
2007 BMW Z4 Convertible 3.0si 2dr Convertible (3.0L 6cyl 6M)
Beware of Z4 deficiencies!
 This review focuses more on the bad... fragile paint (scratches too easily), mostly plastic (can't wax out those scratches), annoying beeper (won't shut up for 1 minute, no chimes!), seat belt can't be adjusted (irritates neck), runflat tires sensitive (added air twice in 4 months), 6 speed manual doesn't shift smoothly, doesn't hold value (depreciated $13K < 4 months, so I'm stuck!), steering keeps driver way too active, ride quality on rough roads is unacceptable (feel every imperfection!), noisy with roof up, rattles.  BMW engineers have ruined this car! Our 2003 Z4 was superior!  Yep, I have high standards, especially when I pay $47K+ for a new BMW!