I forgot to mention after my post on 12/28 that Ed Voyles Hyundai came back with a very aggressive offer, made up for the shortcomings of that initial experience, and ultimately made the Equus irresistible.
The problems with the vehicle's shortcomings still exist, of course--but I've become all too aware that there is no perfect vehicle for me. I've driven a BMW, a Mercedes, an Infiniti, a Lexus, an Acura, a Cadillac, a Lincoln, an Audi, a Volvo, a Jaguar, a Range Rover, a Bentley (okay, I never even for a moment considered buying it, but they were willing to let me drive it, so why not?...), and a Porsche as well as the Equus, and there isn't a single one of them that doesn't have problems and shortcomings. Let me pick and choose features from each and I could build the perfect car... but that's impossible, so I have to determine the best combination of features, performance, comfort, and price.
The Equus ultimately won out. At the price they were originally asking, the shortcomings made it an unacceptable vehicle--but at the revised price, complete with a full ten-year extended warranty, the positives outweighed the negatives. So I now have a black-on-black Equus Ultimate, and we've thoroughly enjoyed it so far. Between this car and the Acura MDX, I think I have the best combination of price/features/performance/comfort available.