So, im not a huge nudger. Not opposed to it, dont feel like it is cheating, and don't care if others nudge my machines.
I guess the real reason why i dont personally nudge is that i have a T2 and a DM that are both in good condition. Then a couple of years ago I was at my uncle's house watching him play his space station (about 10 years older than both of my machines), and I stood there and fear watching him play convinced that the back box was going to snap off at any moment. The combination of sights and sounds was stressful because everytime he nudged the machine, i envisioned the backbox snapping off.
Ever since then I have avoided nudging on privately owned machines. This is mainly out of the respect I have for the amount of work owners have put into their machines.
On the other hand, it seems like I'm constantly losing money playing half working machines out in the wild, so I am much more willing to nudge. If the owner can't bother to level the machine or if it is clearly just pieced together (wrong coil strength etc...) then ill nudge. If the owner doesn't want to take care of the machine and all they care about is stealing quarters I'm not going to go out of my way either.
With all of that being said, I can't think of many examples where nudging has led me to get a drastically higher score than I otherwise would have gotten, so it doesn't really matter to me... or maybe I'm just not very good at it