RE: Narrowed down to 3 guns, what do you think?
Of the three rifles you mention I would have to go with the H&R Sidekick. My reasons are;
The Tradition's Pursuit just came out and I would avoid if for that reason alone until I was sure all the bugs were worked out of the rifle. Also not enough posts are on the rifle to give one a good idea of how well it is working for everyone. It takes time for them to break down. Also I have heard that the triggers on the Pursuit are not all that great. Many of them need trigger jobs and Traditions is working on a better trigger.
The Beartooth Magnum... who makes it? What is really known about it? How many favorible posts have you read on it? Granted the price is nice but do not always buy on price.
The H&R Sidekick on the otherhand is made by an excellent company that has been in business making this kind of action on rifles and shotguns for many years. I have read some excellent reports on the trigger pull of the rifle being outstanding. I have shouldered the rifle and it is very well balanced. I also liked the fiber optics sights on the rifle I was looking at. I have also read posts of great accuracy with the Sidekick and the Huntsman.
Being the style of muzzleloader your picking they should be a little more cleaning friendly then some of the others out there on the market. Also the Bushnell Banner Dusk to Dawn scope is an excellent choice. Good quality and excellent light gathering. I was looking at one with 6" eye relief, but decided to go with a RED DOT instead since scopes are not legal in Wisconsin....
The H&R should be an excellent sabot shooter with the 1:28 twist barrel.
Good luck.