I've been to Allentown the past 2 years. Definitely worth attending!
If you bring an AFMr SE it will be nicer than 99% of the other machines in free-play. This is not to say there aren't nice pins in free-play - really nice, well maintained machines do turn up - but there are also a fair share of beaters looking to get offloaded. Last year I wanted to buy a lower-end DMD and there was so little to pick from I went NIB instead.
I personally wouldn't mind bringing any previously routed machines to a show - another 300 games is not going to hurt them, and if it did, I would have broken it myself anyway.