I think any of those options will do what you need them to do. If you're looking for a BP revolver for purely utilitarian purposes, go for the Ruger if you can find one. If not, I say the Remington. Good and sturdy, and . I like the Colt style guns plenty, but the Dragoon pistols are a bit on the heavy side for carrying all day. As for the 1860 Army, it'll handle BP fouling better than the Remington generally, but I don't think you're going to be firing off more than a cylinder. If you did, you can swap cylinders with a Remington (a purely modern practice, but it works), though I wouldn't carry the spare cylinder capped.
Granted, the 1860 feels more comfortable in hand than the Remington in my experience and won't rap your knuckles, so both have their advantages.