I own both E9 (71 CS auto - since '87) and E24 (80 UK-spec 635CSi 5-speed - since '90) and I wouldn't necesarily rate one over the other as far as reliability is concerned. Most of my repair issues have been just standard wear & tear over the years. Although the 6 fractured the flange that connects the front pulley to the crankshaft - not a particularly expensive exercise, but a bit worrying... I'm strictly an amateur mechanic, but I too feel a little intimidated by the potential of the 635 repair issues. Electronic ignition doesn't help, but I think the complexity of the car will prove to be more of a problem as the years roll on. I'd certainly never touch a Motronic/DME-thingy car unless someone else was paying the running costs. To stretch the example - how would you like to be trying to run an 850i on a budget in 15 years time? Yes, the 6 is the better car, but only in the sense that it's a generation newer. The E9, I'm sure will be able to run (mechanically) forever - it's just the bodyshell issues that are the trouble. If it's any consolation to anyone, I visited the Karmann factory way back in 1990 and managed to talk my way into their museum. When I found the E9 they had on display (beside a 6er) I dropped to the floor & peered underneath. Not a pretty sight! Their car wasn't in any better condition than mine! cheers, Graeme