You are correct. The Genesis Coupe is really a great vehicle. A friend has one and I drove it the other day.That was ten freakin' years ago. Hyundai is not even comparable to the company it was ten years ago. I know their reputation used to blow, but I'd suggest doing some research and you will find that is not even close to being the case anymore. Your last sentence makes me question the last time you were in a Hyundai, their entire model line is very well regarded. (No, I don't drive a Hyundai, nor does anyone in my family, heck I don't think I know a single person who does. And I don't work for them either)
The Genesis Coupe is widely regarded as the best car in it's class by a large, large margin. And underpowered? Are you kidding me? This car can run dead even with a G37 or an IS350 in a straight line when it has the V6 or a chipped version of its 2.0T. The four banger puts on 210 HP (comparable to Audi/VW's renowned turbo 4 cylinder) and the naturally aspirated 3.8L V6 puts out 306 HP (putting it on par from a HP stand point with cars like the BMW 335i, G37, IS350, Audi S4/5) hardly underpowered I would say. It's RWD, and handles like any really good sports coupe.
Fit and finish is also top notch, a fully loaded G-Coupe with all the trimmings and goodies will run you between 33-35k and be worth every penny. Heck the damn thing can be optioned to have brembo brakes and a limited slip differential which is something a sports coupe like the BMW 335i lacks (but is standard fare on the legendary M3). This car is not a sleeper and it most certainly is more than just "passable" when comapred to cars in it's class.
In fact, when edmunds.com (one of the most well respected car sites in the world) compared a fully loaded G37 vs. a fully loaded Genesis Coupe, the Genesis Coupe won, even though there is nearly a 10k price difference between the two cars.
I'll say right now, Hyundai might be the best car company in the world right now. They are certainly making Honda and Toyota look downright foolish with a new and refreshing product line, and the Genesis Coupe is the masterpiece that pulls it all together.
The Genesis Sedan is also regarded as being a legitimate alternative to cars like the 7 series and Mercedes S-Class. It's just a really solid product line that Hyundai puts out, they aren't even comparable to the car you drove ten years ago, and frankly most of your statements are just downright incorrect now about the company. Oh did I mention the Genesis Sedan was the 2009 North American Car of the Year? But yeah I suppose that is just passable...