IMO, if it has a good lock on it, you won't see much difference with use.
The hard surfaces of the sear and tumbler won't wear or polish much just from use.
To find out if the lock is the problem, remove it from the stock. Bring it to full cock. Keep your fingers out of the way of the hammer (if it is a flintlock, close the frizzen and keep your parts out of the way of the cock and the frizzen).
Push upwards on the sear arm (the thing that is sticking out from the inner surface of the lock face).
Pay attention to how hard you had to push for the sear to release and the hammer or cock to fall.
If it's more than a few pounds, the lock is the problem.
If it's not more than a few pounds the problem is with the location of the trigger pivot pin.
If you want to be PC, then just smile and tell everyone your trigger pull is "just like the originals!" ::