I have a Brazilian replica 1803. I feel it is about 80% wall-hanger and 20% practical. The lock is unreliable. I get only about 6 shots per flint, the double throated cock design makes it non-adjustable. Flints that are long enough to properly adjust in the jaw are too wide and look funny. Mine shoots very good groups, but I've spent a lot of time at the range finding the right load - still its unreliable. Ramrod is not threaded and cannot accept jags or worms. Sights that came with mine were total junk - both had to be replaced. It is my opinion that these replica guns are highly overpriced junk. I got mine through an outright trade, but if I had paid $500-600 for it, I would have been really bent out of shape. I have no information about any American made replica 1803s so I cannot comment there, but do whatever you have to in order to save enough to buy a reliable piece (which probably means a custom gun) Before you buy a foreign replica, handle a custom gun and get to know a custom gun maker. You will need no further convincing after you operate the locks on a replica and a custom. For a few hundred dollars difference, you can end up with a reliable, functional, beatuiful flintlock, that can be handed down to the next generation. I can tell you that if it weren't for my friend talking me out of it - twice - my replica would have been at the bottom of the pond at the farm where I hunt. Respectfully submitted.
(I traded for my 1803 to see if I was going to like the idea of a flintlock. I did like it - a lot. I like the complexity of the system, i.e., ball, load, patch, flint spacing, timing, etc)