Hi,
Well call me old fashioned, but I have accommodated my lack of illumination by either...
Turning on the rear fogs
Turning on the hazards
Putting one foot on the break pedal
Opening the drivers door
Opening the rear tailgate door
Getting someone to see me back
If I could find some Canbus LED's it would be helpful, but really on such an excellent car, I can live with poor reversing lights...
And yes they have fixed the issue on the new RX 450, which if I had some spare cash, I would upgrade to! For now the bulb upgrade sounds more attainable.