Love the RX300 EXCEPT for the rattles, have been plagued with these since about 1500 miles. Dealer has tried and tried but cannot fix the rattles, more just appear. Gonna trade this one in which is a shame because, otherwise, it is a great little ON-road SUV (also own a GMC Yukon 4Dr, 4WD for serious duty). The fuel mileage is a bit disappointing too, but it is AWD so I won't say it is awful (18 city 19-20 highway).
Driveability, easy to manuever, looks sporty(you must have the rear spoiler, makes a big difference), heated seats are addictive.
FIX THE RATTLES. Let the passenger program NAV system while in motion. The car knows when a person is in the passenger seat, use that information to unlock the NAV lockout. More engress room, constantly kicking (and scuffing) the seat and door panel and I'm only 5'11".