I agree that NOS should mean that the watch has never been worn. A watch that has been worn is, at best "like new". A NOS watch should be fine if kept properly.
If it were me, I'd go ahead and wear the watch until I had reason to send it for service. My 2526 has been in Geneva since January for an overhaul. It would stay wound for only about 15 hours a day, so I knew it was time for a tune-up. It is somewhat expensive, being more than my first three cars and two watches combined. But the time it is taking has given me a good opportunity to search for an original "PP" crown - mine has a replacement crown. And pick out a new band. And a NOS buckle.
Fortunately I have many watches.