I think the serviced watches are a grey area - you'd hope that the service could be done without leaving tool marks. But if there are a couple of marks that's preferable to a movement that has been done in by being forced to run with no oil - if the movement has to be replaced, then the NOS status comes into question. If the watch is relumed, then it is no longer NOS as far as I am concerned.

To set my stall out, I don't have any NOS watches myself. I have mint watches and I have a couple of fairly knackered watches at the other end of the scale. While I can see the attraction of a watch in the best possible condition, I am going to wear said watch and immediately render it no longer NOS in any case, so I personally would probably prefer to put some of the premium I would have to pay for NOS into the next watch. Don't get me wrong, it's not really a quantity over quality approach, I take very good care of my watches once I have them and I very much value originality - ultimately, probably over condition.