NEF huntsman or sidekick muzzleloader???
I'm blanking on this, but I believe one is capable of shooting a magnum charge, and the other isn't. Keep that in mind, if it matters to you. It wouldn't matter to me. I'll never use 150 grains of powder!
You might look into a Combo, if that interests you. For a little more money, you get a huntsman with either an extra 12 ga. barrel, or a .243 barrel, I think.