Quieter ride. The old 2002 X5 had a lot of miles but it was very quiet. The Passport has window noise above 30 mph, like the window is slightly open. The suspension is also noisy at low speeds in the PP.
While I have no doubt about BMW's being quiet, having driven two over the last 16 years, the PP is very quiet, the Elite & Touring have something called Acoustic Glass, which is supposedly quieter than the Sport & EX models..
Which model do you have? You may have bad rubber stripping, someone else here had that and had the dealer fix it...