Acura's biggest and most powerful sedan is a very nice ride. I'm not sure that's enough to make the car stand out in a niche full of really nice luxury sedans, though.
Still, you get a lot of niceness for your after-tax disposable income.
The RLX succeeded the RL a few years back, a luxury sedan I liked a lot, and this replacement has much to recommend. Oomph is plentiful, comfort and luxury abound, and the car will probably outlive its owners. So why do I come away from a week with it feeling kind of "meh?"