 My '99 Z3 (bought Feb '08, 48K miles) still looks great on the outside and powertrain has held up well.  Surprised that interior plastic parts are so chintzy, such as loose power drivers seat, cup holder cover, and cracked/broken seat belt restraint and parking brake handle. Radiator fan shroud also cracked and broke off.  6-CD changer in trunk has poor tolerance for bumps.  Would not have expected all these issues at 49K miles.