I've often driven my fathers. If it tells you anything, I enjoy driving the ls460 on occasions (but could never imagine driving one daily) while my father hates when he drives my 335 (or my wife's x5). His last 5 cars have been Lexus LS4xx, and he keeps cars for 4-6 years (or until someone t-bones him).
The whole car is significantly more intuitive than any given BMW, the easiest example of which being the navigation. Reliability and maintenance costs are also a major step in the right direction. It has MUCH lighter steering than an e60 and is much less communicative from the suspension or steering, but it does have surprising pickup for such a huge, soft car. Road noise, and interior quality (and sound system with Marc Levinson) are also a step above (or several) the BMW. That said, I like to feel like I am driving, not boating
