Insurance isn't bad at all on these cars, I pay $400.00 / 6 months.
I get 20 city / 27 highway out of my 3.8 and I "DRIVE IT HARD"
No knocking or " detuning " it's gasoline direct injection. I ran premium a few tanks and have been running regular for two years, no change in gas mileage and no noticeable change in performance so why bother paying for premium. That this car can run on regular is a MAJOR plus.
Actually the ECU will detect your octane and adjust not only to it, but your driving style as well. Upon a "fresh" reset it'll be more aggressive right from the start. Only after it "learns" your driving style does it give both the performance and mileage that best suits your style and fuel being used. If it's reset to factory specs, and you run regular it'll knock, (at least until it adjusts to the lower power and octane settings). Just as if you put premium in and it's been running on regular it'll not give you those extra ponies right away (and be a waste of gas until it's been reset).
I know my G35 has done this for years. In fact, if you swap to higher octane gas, (
or lower for that matter) the fastest way to get optimal performance is to reset the ECU, either by disconnecting the battery or the gas pedal method (which I use). I suspect the Genesis has a very similar method.
G35 ECU Reset
1) Turn ignition to on only, (don't start) wait 3 seconds
2) Push fully and release the gas pedal 5 times within 5 seconds
3) Wait 7 secs, fully push gas pedal and hold for 10 seconds until the CES light starts to blink
4) Release gas pedal (you are in diagnostic test mode 2)
5) Press and
hold gas pedal for more than 10 seconds. Release pedal.
6) The CES light will continue to blink
7) Turn ignition off. Restart car.
This is direct from J.D. Power:
1.) Hyundai sells the 2013 Genesis Coupe as a 2.0T model and as a 3.8 model. The Genesis Coupe 2.0T is equipped with a turbocharged 2.0-liter 4-cylinder engine that gains new twin-scroll turbocharger and a larger intercooler for 2013. Horsepower and torque increase substantially, generating 274 horsepower at 6,000 rpm and 275 lb.-ft. at 2,000 rpm, operating on premium fuel.
The engine's anti-knock sensors are designed to automatically adjust ignition timing and engine mapping to allow the engine to run perfectly on regular fuel in exchange for downgrades in power to 260 horsepower and 260 lb.-ft. of torque. Hyundai claims the Genesis Coupe 2.0T achieves a 146-mph top speed while returning 21-mpg city/30-mpg highway with the standard 6-speed manual gearbox, which offers improved shift feel and clutch operation for 2013. With the new 8-speed automatic transmission, developed in-house by Hyundai, fuel economy ratings are 20-mpg city/31-mpg highway.
2.) The Genesis Coupe 3.8 is equipped with a 3.8-liter V-6 engine, now equipped with direct fuel injection for 2013. Horsepower increases by 42 ponies this year, to 348 horsepower at 6,400 rpm, and torque is up 29 lb.-ft. to 295 at 5,100 rpm when burning premium unleaded fuel.
On regular unleaded, horsepower drops to 344 while torque measures 292 lb.-ft. The V-6 engine is paired with a 6-speed manual gearbox or the new 8-speed automatic transmission, and fuel economy improves to 18-mpg city/27-mpg highway with the manual and 18-mpg city/28-mpg highway with the automatic. Hyundai says the Genesis Coupe 3.8 accelerates to 60 mph in less than 5.5 seconds on the way to a top speed of 149 mph.
rops: OTOH the gas mileage you're going to have to get used to. 
But honestly that's the only downside. Ehhhh maybe the insurance but who's counting.... other than your insurance agent that is. 
). Glad to hear you're truck is an option for this winter! 
