x5 5.0 has pretty much the same HP as x3 M. with torque low where it matters for a heavy SUV.
M car treatment for SUV is a tough one. One can not really track a 2 ton vehicle. So you are mostly trying to utilize it on the street.
But at the same time you are getting very stiff suspension, potentially uncomfortable seats (again great on the track) and the HP and Torque are very high up there - 7200 RPM. So one needs to rev the heck out of that engine to outrun the X5 V8.
So i'm sticking with X5 and maybe towing Mazda Miata to the track or an M2
