Yep, they're very reliable. There was an issue with the cylinder head bolts on the pre facelift cars, probably about 1 in 100 had issues with the head bolts failing, but this was resolved with a different head bolt design on the later pre face lift and face lift cars, there's plenty of info about it online, even down to which engine numbers were affected. They a great drive and verging on super car performance even when standard 0 - 60 in 4 seconds dead, very easy to tune as the C63 engine was an electronically detuned E63 engine, so a remap takes you to over 500bhp and a sub 4 second 0 - 60. Really good german build quality and capable of high mileages. For me it's that V8 rumble that I love and these have one hell of a rumble. The surprising thing is that there are lots with very low mileages (Probably due to the fuel consumption, so not used as an everyday car by many). Mine is a weekend toy and a bit of a garage queen I hate to admit. But once you've driven one, you'll want one. I always loved the BMW E60 M5 (V10 Engine) and they were my dream car, I went out with the intention of buying one, one of the dealers I went to look at one also had a C63 along side the M5 and he suggested I take that for a test drive to compare it with the M5......... I'll be totally honest and admit that the C63 was the better car by a mile, the M5 you needed to really rev it to get the performance, it felt like you would always be thrashing it to get the performance it had, and the gear changes were aweful. The C63 had instant torque and power and the gear changes were sooooooo much better. A month later I'd bought one, not the white one I have now, but a silver one. Love them some much this is my second C63. Best thing is to take one out for a test drive.