In Ohio, where those two and pistols were the only choices for many years, my son opted for the muzzleloader over his smoooth bore 20 guage. Its far more accurate, and gives a lot more range. If the 20 were rifles, and shooting saboted slugs, the range difference would not be so great.
If you are hunting in an area where shots under 100 yards are typical, the big bore muzzleoader is probably more effective than most rifle cartridges for dropping them faster. I do agree though, that if you have $200, and you are looking for greater distances well beyond 100 yards, you can easily an old military rifle in 8x57, 7x57, 303 or some other used rfile that will do a better job.