Personally I would avoid the Traditions unless the cost is your prime consideration. They are pretty basic no frills what guns made to pretty minimal design standards. Pretty plebian guns imo.
Go to Mid South Shooters Supply and look at the Lyman "Great Plain" series. You have a choice of .45, .50, .54 caliber; percussion or flintlock ignition; left or right hand action; and 32 inch 1 in 60 twist, 1 in 32 or 1 in 28 for conical bullets. And I think they make a 28 inch or 24 inch barreled "carbine length" model as well.
The Lyman guns are considered in the Rendevous/Mountain Man re-enactors circles as being pretty darned accurate replicas of long-rifles from the era. And they are very accurate with either the round ball or conical twist barrels. Also Green Mountain makes precision after market barrels that are drop-ins. (At least they did 30 yrs ago)
You can spend twice as much on your kit gun as a Lyman, or you can spend half as much (Traditions). Having owned multiple Lymans, a Navy Arms carbine "Hawken" and a custom built flintlock, I would go for the Lyman.
Sadly Thompson Center Arms no longer makes their excellent line of Hawken style rifles but you can still find them very reasonably priced on the used gun market for less than a kit.