We have a pretty similar car history. I also went from Mercedes to Lexus. We have a 2007 LS 460. We've only put 45,000 miles on it over the course of 8 years of ownership so I'm thinking it will last until I'm well into old age. I'm not sure if I should be elated or disappointed
Our 1995 E320 hit 90k miles before we called it quits in 2006. We replaced that one with a 2006 Honda Pilot.
The Pilot and LS 460 have been pretty good to us. The 2007 LS 460 was a first year model, but in light of that it's been pretty good to us. We've had 2 non-maintenance problems over the course of ownership. The driver side and passenger side rear view mirrors wouldn't "fold in" properly after parking and locking the car. That cost $700 to fix. And then we had uneven brake pad wear, but that's our fault for not breaking them in properly to begin with.