ElVee

I have a touring with the heated, leather seats. I'm about 6' and 240lbs, and I'm probably at the limit of what I'd find comfortable when in the seats. You definitely should try it out, and just sit in the car for a while. Play with the adjustments and, if touring, the lumbar support handle on the right side. Some people get tired of the ride after a few hours. I personally have been driving for 2-4 hours a few times and I am fine.

I have plenty head room, and plenty other room for legs, knees, etc, and I can move around into different positions on longer drives just fine. I do wish, however, I could telescope the steering wheel.

Older models (2009-2011 is my guess) have had complaints about consistent road noise being annoying. My 2013 is fine. I think the consensus has been Nissan has quietly improved the sound dampening over the years. Going for a test drive is tough to figure this out, since you'll hear things you don't hear on other cars for the first few weeks (rocks in the wheel wells, exhaust just because it's fun, quite a bit of rain sound if you're in the rain). If you can upgrade this on your own, then don't worry about it.

That said, if the roads you drive on suck, you will feel it. Uneven, cracked roads can get a little busy...well...ok, downright violent. Bad backs need not apply. Then again, the Z is a sports car, not a normal pleasant car that happens to go fast. This is part of the type of car you're looking at.

Sadly, all of this is just me, and is completely subjective to what you like. If you can find an acquaintance that has a Z to do an extended drive with it, I wholly suggest it. Or even find a place to rent one for a week.