You are right in the fact that the Lexus had a lot of upcoming costs in addition to fuel economy. I had a '96 Lexus ES300, and by 125k miles, the repair bill was 1,5x the value of the vehicle. Stuff like a new steering rack, struts and shocks, leaks, etc.....

So a better drive, lower maintenance costs, and the latest technology. And you get a side benefit of lower fuel consumption. Win win!