I think a Saskatchewan fellow, NSX2398, is the guy to ask. I believe he DD's his NSX all year long. Lucas
That would be me. Wow .. you actually found another NSX that's winter driven .. and it's for sale. That's about a rare as hitting the lottery.
But joking aside, I'm somewhat biased (and probably alone) in my thoughts about the impacts of winter driving .. although I do have probably more than 30k+ miles of winter driving on mine and it's close to 190k miles so I also have more practical experience with maintenance considerations of winter driving than probably anyone else you'll find.
First of all, as Bram said, a well documented maintenance history is the first thing you want to look for .. but that's important whether it DD or not; winter driven or not.
Second is to have a realistic assessment of how much road rash you can tolerate. Where I live, winter driving means sand on the roads as well as salt so you're likely not getting something that you're going to win shows with. I do my best to protect it with a front bra and mirror bras .. but the paint likely isn't going to be perfect but a good detailer can probably fix some of that
Thirdly .. based on my experiences I can't honestly say there's anything maintenance wise that I can say conclusively that was a direct cause of winter driving .. with the exception of the CD player which gave up after about 3 years of playing CDs in the trunk (which is unheated) at temps down to -30; and maybe the oil pressure sensor switch which I've had to replace a couple of time. I've had to change the A/C compressor; upgraded the ABS system; fixed the Bose amps; etc but those are all things that are typical NSX weak points. And as I've said elsewhere, I put about 75,000 miles across 7 years on the timing belt which had started multiple times at temps down to -40 (which I consider to be the worst stress conditions you could possibly put it under) and when it was replaced by one of the best techs in the US, he said it didn't look any different than anything else he sees. He did bitch though about putting the headers on and replacing the main coolant hoses to the front but that was more because when the block heater was installed, they wrapped the cord around the hoses. Haven't had any issues (knock on wood) with the clutch, brakes (over than ABS), fuel pump, alternator, coil packs .. and I might even be running on the original shocks. I did have some strange ECU problems which required replacing it but it had been mod'd to have a Prospeed chip and Prime has been littered recently with people having strange problems after getting chip'd. Oh .. I know one failure that can be attributed to winter .. the struts that hold the trunk and glass over the engine .. but that's pretty common for any vehicle in Canada that has hatchback-like supports. BTW, test the windows to make sure they still go up and down. When it gets cold, they can go up very slowly. I did the Huga window mod things which I've been very happy with.. although a lot of guys do that who don't winter drive.
Lastly, it would be a bonus if the owner ran synthetic consistently in the winter months and changed filters at least twice a year. But honestly, I might be in the minority but I believe that using the NSX as a DD keeps everything 'exercised' which leads to better lubrication, etc and generally less problems. I seem to have way less battery issues than most people who park their cars .. and mine has to put up with a lot of cold cranks.
Hope that helps ...Ian