FWIW I always use the Auto Hold button instead of the Parking Brake lever when parking. The Auto Hold feature stops the lurch when you turn off the engine on a slope.
Funf Dreisig
EDIT: My Bad.
I’ve been using Auto Hold on our sloping drive, while I get out for the mail, for over a decade. And Auto Hold DOES hold the X5 rock steady. BUT… I don’t turn off the engine until I get to the garage — on level ground. Today I tested turning off the engine with Auto Hold on at the mail box and sure enough the X5 DID lurch down hill.
FWIW I also use Auto Hold in the garage because it reduces the wear and tear on the parking brake handle.