Even though the kits look easy, they can take alot of time to do right. Patience is the most important tool you'll need.
If you learn what you are doing, there are things you can do to tweak the kits to make them better than a factory finished unit.
Remember that the minimum caliber is 50. Some of the kits offerred have crude locks and some are better grade. Trigger pulls can be pretty stiff.
A traditions trapper has a hefty barrel and is rugged enough, but a bit heavy. It does have set triggers. The kentucky pistol has a lower grade lock and thinner barrel so it won't take heavy loads like a trapper. The Pedersoli is a bit better quality, but more expensive.
Shop around seriously, some on-line suppliers have great prices. Traditions runs closeouts on their web site as well.