Basically, I'm just wondering how reliable these cars are and any problems I should be prepared for. We had a 1987 BMW 325 for about twenty years. It clocked up over 225,000 miles without a single problem, so I'm wondering if that sort of bulletproof reliability stretches to BMWs other models.

Is there any model that's more reliable than another (ex. 525 vs. 530 vs. 535 vs. 540)?

Appreciate the info!