Nissan would be a pretty reliable car until about 100k miles and same goes for the Genesis if you have to buy one of those check them out the Maxima is more of a rocket ship while the Genesis is more luxurious they both tend to have issues after 10 15 years. Either way have a mechanic check it out before purchase to make sure it is in good shape you don't want to buy someone elses problem. If I personally had to choose I would look for the best deal lowest mileage 2011-2014 Nissan Maxima I could find the Hyundai is not my style really. 

To check what years have the most common issues check these sites:

https://www.carcomplaints.com/Nissan/Maxima/

https://www.carcomplaints.com/Hyundai/Genesis/

To give you examples here is the 2012 Genesis and 2010 Maxima:

https://www.carcomplaints.com/Hyundai/Genesis/2012/

https://www.carcomplaints.com/Nissan/Maxima/2010/

I would stay away from the 2010 because of steering issues and consider a 2011-2014 and the Hyundai is just a meh either way it will fall apart after 100k miles they have lower quality. Transmission failures are the most severe and common issues with Nissans so look out for that check this page out: https://www.carcomplaints.com/Nissan/Maxima/2011/transmission/premature_transmission_failure.shtml

Hope this helps!

Genesis is nice, as cool as the Nissans will be for a while, over 100,000 miles and they will start to fall apart.  The Genesis would be good.  How long are you planning to have these?

The maximas  are nice and they are a rocket ship to drive but if it’s only for fun a rear wheel drive will always provide the most excitement