As someone who has a close friend who has the new Genesis and I have to tell you this. First the 3.8 is a nice engine as it's not just for Hyundai but also shares it with Mitsubishi and KIA. When the engine was revealed it was a "breakthrough" for the 3 being that it was a small engine with tons of power..So stated.
First let me say this...As other posters have said the Hyundai is exactly that...Look at it's history not very reliable or great. Granted in the past few years KIA/Hyundai have all made advancements in there looks and performance but at the end of the day they are still a KIA and Hyundai.
Second as I stated I have a close friend who went with the Genesis (due to the price)He later realized how unreliable and cheaply made it was. After the first 10 thousand miles the front grill started having major issues(I.E coming apart).The front headlights went out on him numerous times.The leather seats actually started to tear.The navigation in it was horrible always loosing signal.His so called "breakthrough" engine had major oil looks. Lets just say after 50k miles he brought it into a Infiniti dealer and only received a 14k trade in for a 3 year old car that he paid 33k for.It's sad really because according to KBB it was worth 17k but he didn't care he just wanted to get out of it.
I also drove the car and truthfully.It's not even a comparison at all I have owned everything from a G35 with 420whp to a M3 to and S4 and I have to say I was never a fan of the M I always felt it was big and slow. Yet after getting into mine these last 3 months for a steal of a price. I love it! It's smooth heavy yes but still accelerates amazingly.The comfort is just out the door for the year that it is..The electronics in it(I.E Nav,Bose system surround sound).Seem properly made while in the Genesis it was was all bulky and honestly ugly and the sad part it looks as if there trying to copy Infiniti (
http://www.carbodydesign.com/archive/20 ... r-2-lg.jpg) vs
http://www.yocar.com/blogs/general/uplo ... 793594.jpg
In the end it's all up to your taste but as some have stated comparing these two just doesn't happen.