If you want to do the V Max events and pass 200 then speak to Acid at MSL who is a regular with various bits of kit (including the supercharged C63 BS). Acid can give you the remaps and other mods you will need, even a stage 1 will get your limiter removed.
My E63 with only a stage 1 was running 704 BHP but I never got to an event to test it. I was more interested in mid range and torque which was astounding!
haha!I wonder how high a cliff would have to be for me to push my car off to get 200 MPH
I don't think you can remove the speed limiter with Xentry. There is a speed limit field that can be modified but it has a maximum value of 250kph (155mph). It's useful on vans and the like but not on the 63's.