I owned an RX 330 and traded it for a MB. I traded the MB two months later for the RX 350. It is true, you do not know what you have until it's gone. This should be enough said but I'll go on. The RX 350 is the perfect car. The XM/nav/rear camera, etc., work in concert and flawlessly; very easy to operate. Engine power is very adequate with pick up when you need it. Love, love, love this car.
Navigation, Bluetooth, engine and handling, 18" wheels.
Integrated console armrest would be nice in lieu of fold down seat armrests that are somewhat small. But most importantly, add iPod/Aux -- this is all that's missing.