I was able to test drive the 28i twice and the 35i (non-Sport) three times, and my wife drove both once. The dealership had one of each that my salesguy claimed were there exclusively so that prospective buyers could drive each one extensively. They actually were BMW Canada cars. I took both cars without salesguy along, and for at least 1/2 hr or more each time.
Seems strange that the dealership you were at had none to drive. Too bad. I have driven the Q5 and prefer the X3 from a driving dynamics POV.