RE: When does the nevousness stop?
It's never really left me, either, though I'd describe it as a "heightened sense of alertness", rather than nervousness.
'Cept if it's a new model, of course. Then it's a mix of apprehension and reluctance and determination and fatalism.
If I haven't flown for a while, something marvellous happens. As I drive to the flying field and catch sight of models in the air ... oh, do I get a buzz. And then the smell of burnt fuel in the pits. Whoa! Absolutely the most fun you can have with your clothes on.
Or, perhaps, I'm a bit odd? 26 years and counting.