Heck of a rifle in smokeless muzzle loader, the best affordable one as far as I can tell. I got one a few years back. Crushed about 6 deer with it so far. I would take mine on safari if I could go : ).
I have seen the nice stainless ones recently go for about 1000 bucks, the others are bit less.
They wear out the vent liner. It is a cheap and easy to replace wear item. My rifle with an xtp and mmp sabot will easily shoot under 2moa at 100 yards pretty much every time I dont screw it up. Many groups are better, and I am sure a better bullet will tighten that up too, but the XTP is brutal on deer. As for velocity, I am shooting a bit over 1800 FPS I believe it is, with more on the table.
The 45/70 bullets with proper MMP sabot (orange I think) do great if you are after tougher game. I have used the 240g 44 mag and 250g 45 cal xtp bullets with great success on deer. Parker productions makes an honest to god long range bullet at well with a REAL ballistic coefficient (near .40) with good terminal performance. I have a few and hope to try them out this year.
Don't be concerned with a lot of the Wakeman stuff you read online. If you go through all of it you will see it starts to look A LOT like a jilted ex employee kinda thing. You will not have any problems unless you load ridiculous duplex and triplex loads (what was reportedly done beforehand in that case, though later denied).
I have about 900 shots through mine, and it is undoubtedly one of my favorite rifles. Very cool to shoot. Spend a little time with the rifle and it may grow on you.