I drive rather low reved... Mostly at about 2.000 rpm the gear is changed. At 50 km/h (approx. 30 mph) I'm already in 5th gear.
The engine has abolutly caused no problems what so ever. The gearbox - well, I don't talk about it. What my biggest problem in the C30 is, is basially the front suspension. The top steering bearings have been changed so often, about at least once a year... of course, both sides... My AC had a sheared pipe and didn't work. My drivers seat clicked/clacked in curves. My steering coloumn rattled quite heavily. My headlights get damp from inside and are currently filfthy (from inside!). The fogs are basically blunt.
Otherwise... All fine