The 1858 Remington can be had in both traditional fixed sight and adjustable sight target variants and can be had in both blue and stainless steel. The top strap design means it is strong, and it is also accurate and easy to clean. Caliber is .44, which is usually .454 in an 1858 replica. If you're looking for a first percussion revolver, it's arguably the best choice.
The 1860 Colt Army is a Civil War classic, open top revolver. They are fun to shoot and are very nicely balanced. However, accurate replicas will also shoot to a point of aim about 80-100 yards down range - since they were designed for the tactics of the time with troops in lines about that far apart. For close range self defense shooting the zero didn't make a difference. As a range toy, you might not be quite so happy. Caliber is also .44, but this varies from .451 to .454 deepening on who makes it.
The 1851 Navy Colt was normally in .36 caliber but replicas are also made in .44 caliber. It's an open top revolver with a wedge, like the 1860 Colt. They are even better balanced than the 1860 and are fun to shoot. There are often brass frame models, and while they are less expensive, they don't hold up as well.
On the larger end of the scale you have the 1847 Walker, and the 1st through 3rd Model Dragoons. The 1847 Walker is more common on the replica market, followed by the 3rd Model Dragoon and both are great fun to shoot. The caliber is also .44, which in the Walker replicas I have owned is .457". The Walker and the Dragoon Models are all horse pistols designed to be carried in a pommel holster by cavalry troops. You can get a holster for them, but it's 4 1/2 pounds of pistol, so be sure you use a really well made belt if you plan to carry it that way.
In between the 1858 and the horse pistols you have the Ruger Old Army. It is arguably the best percussion revolver ever made, and they use a .457" ball like the Walker and Dragoon model pistols. It was built on the Ruger Blackhawk frame and it is very strong, and also very accurate by black powder standards. They were made in both blue and stainless versions, but sadly they were discontinued in 2008. They still show up on the used market in very good to excellent condition but plan on spending $500-$600 for one.
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You tend to get what you pay for, and the major difference can be found in the quality, hardness and durability of the fire control parts. I've owned a few Pietta made replicas and I've had very mixed results with them. A couple have been fine, but one was very poor quality and short lived.
Uberti and Armi Sport both make decent replica revolvers.
You can still find some of the Colt Second generation black powder revolvers and they are highly regarded. Colt also had their signature series revolvers and they were superbly finished. They were made using imported Uberti parts that were assembled for Colt by Iver Johnson. Fit and finish is excellent and they are a joy to shoot. They are available in a number of Colt Models including the 1847 Walker and Dragoon models, the 1851 and 1860 plus some civilian models - but they command about $800 in excellent condition.