We have owned the 2006 RX-400h AWD for 4 yrs. We have been very happy with the car. No mechanical problems or breakdowns, much better mileage, about 26 mpg, than our 1999 RX-300 AWD, 18 mpg. Recent safety inspection shows almost no brake wear due to regenerative braking system. Original Michelin Tires have lasted for 54,000+ miles. There are some rattles developing over the years, but nothing serious. Power Steering linkage was replaced by dealership, under warranty repair and at their own recommendation.
We like the great handling and performance in the mountains under wet and snowy conditions. Most conditions do not require chains. Power tail gate is nice, heater seats are useful, and bright headlights make it easy to see at night. backup camera is very useful.
We often need a waste container, like ashtray, which is missing. Blue tooth does not accept all phones, and needs manual setup when changing phones. USB power outlet would be useful with iPOD connection for sound system.