If I had $400 in hand to spend on a muzzleloader, I would be trolling GunBroker for a T/C Omega with a laminate stock.

Reasons:
1. I like the wood. Most accurate and looks the best (IMO)
2. Very accurate once you figure the right load
3. Easy to clean. Does not have the speed breech, but once you get home, a wrench takes it off quick and then clean up is easy, just swabbing the barrel and cleaning the breech plug.

Note, I already have an Omega X7, the carbine version of the Omega, but am looking to pick up the standard with a laminate stock. New, I think they are overpriced, but I realy like the simplicity of the design which will serve as a lifetime gun.

My second choice would also be from GunBroker, a Knight, (either the Elite or Extreme). On that I would settle for the composite stock.

I am a big fan of buying used but have to admit there is a higher risk factor with muzzleloaders.