IDK about the exhaust being throatier or such.
Just wanted to say if its still not enough, you could always throw in a meistercraft or eisenmann. they make the x5 a beast!
BMW and Mercedes Build Beta Products!
Lexus build Release Candidate Products!
Why does this matter?
CAUSE EVERY TIME someone says Lexus has better build quality, one should consider what Toyota their Lexus Engine and chassis platform comes out of and how long that part has been tested in the real world!