BMW's first roadster with a retractable hardtop is now ready for top-down driving pleasure on the backroads of Atlanta. This very elegant rag-top comes in your choice of two models: the Z4 sDrive 30i and the Z4 sDrive35i. The 30i comes with a 255 HP BMW six while the 35i boasts a gnarly 300 HP engine that will get your attention off the line. Yet the base Z4 sDrive 30i has plenty of get-up-and-go, getting you to 60 MPH in under six seconds. That, in our opinion, is a great set-up for North Atlanta byways. The 6-speed manual transmission is a delight as well. Meanwhile, the Z4 sDrive35i blasts to 60 in close to five