The ZR-1 is an amazing machine, plain and simple. It's the biggest, baddest dog in the Corvette kennel, and no doubt it is one fast car. It, like the GT-R, takes on the most expensive of the exotics, and opens a can of whup-a$$ on most that dare to challenge.
Personally, I love the Corvette. It looks exotic, has so much power it's nearly insane, and can be bought from a Chev dealer and serviced there too.
But, the Nissan is like a fighter jet. It's all function over form. Nissan engineers just checked off the boxes of the stuff they wanted, and then wrapped some body work around it, and made sure the aero worked. Fighter cockpits don't have spindly seats or hard to find/use controls. The Nissan's interior is similar in thinking.
Either is a superb choice.