With your speed limit, the 220d is very good, 7.5-8 litres per 100Km, the SE version, a little bit worse with the sport gearbox. The gearbox is smoth, not noisy at all. The new cars dont have any injector problem.
Lexus 220d SE MM owner.
The gearboxes will get noisey over time. I agree they may have fixed the 5th injector issue (or so they say)