That’s what I like about the bimmers, the average person expects a quiet “luxury” car and boom you come in a sedan with a aggressive sounding v8, the slant 6 is also a beauty to the ears, the TT with a burble tune is heaven
You can get the 4.8 up to around 400hp before you need to start thinking about building the engine. You could get a supercharger but theirs only 2 available, one is super rare and good luck finding it complete. And the other is 6000k and not really recommend for the x5, I think it’s because it wouldn’t actually fit in the engine bay.