I've been using a repro Smith for 6 years now for N-SSA Skirmishing; perhaps ~1000+ rds per year; it is still quite tight. I've never had any problems with fouling or leading hampering closing with either plastic or brass cases (neither of which require a press to load; all of my Smith rounds are loading by hand, and I found that if I tried to compress the powder in the plastic cases with a press, they bulged, making loading difficult.) I have seen one, and only one, instance of either a short chamber or slightly overlength brass tubes causing the gun to bind. I use the lighter Rapine, and have experimented with roundballs, both work fine.
A really fun gun to shoot, and though I have read of folks deer hunting with it I have some reservations... 340 grain bullet, 40 gr. max load? Definitely a short range proposition for deer... works great on groundhogs though!