With the 50i or M50i you need to be careful, I've run the speedometer through its full range a number of times. The key is doing so in a safe, isolated place
on the highway here, no one drives the speed limit so you can let its legs stretch into the lower 90's. If I lived somewhere else I'd probably be in the same boat. I still enjoy the V8 sound and power /trq distribution. Either way, you can't go wrong with a 40i. I do wish they offered the DHP on all trims so everyone could experience the best set up.