Jeez, best inline... ask 100 guys and you'll probably get 95 answers. I have an Omega in .50 and love it to death, but my father swears by his Savage. Basically, with ML's you tend to get what you pay for. Knight makes several great rifles, as does T/C. White makes a number of really nice guns, and Markesbery has a whole lines of modern ML's that aren't true inlines, but have direct ignition. I figure the Traditions and CVA guys will gripe that I didn't mention either of those companies, but I still won't say that either company has the design or quality control to qualify as "A" grade gunmakers. I prefer "designed as such" muzzleloaders rather than a centerfire rifle converted to a ML, a la Rem 700 and the like. But then again, that's just my opinion, and my Granddad used to say "Opinions are like A-holes, everyone's got one, and they all stink."
