I recently bought a Pietta 1860 Army revolver (the same brand Cabelas carries, though I didn't get mine from them). I originally planned to get an 1851 Navy, but the place I got mine from only had them in .44 caliber - which I learned is not authentic for that model. I also read that the 1860 is a somewhat superior design - possibly the best design of the Colt percussion revolvers. In any case, I'm very pleased with my Pietta revolver. I suspect the quality of the 1851 would be the same.
I think these represent a great value - I think a modern cartridge revolver of this quality would cost at least $150 more than these cap and ball revolvers. I debated about paying a little more (about $25-$30) to get the Uberti version (Uberti has a long-standing reputation for quality), but I can't find anything to complain about with my Pietta. I'm certainly no expert (this is my first cap and ball revolver, though I've had a black powder rifle for years, and I have a pretty good collection of modern handguns). I've read that Pietta has significantly upgraded their equipment and quality control in the past few years, and I'm certainly satisfied with mine. This is one of those rare guns that I'm enjoying even more than I expected to - I need to put it away so I won't wear all the finish off just from handling it. I think more cap and ball revolvers are in my future - probably a Remington clone in stainless next , then a Dragoon, and probably an 1851 Navy in .36 caliber.
From what I've read and seen, the 1858 Remington design is probably the strongest, easiest to clean, and easiest to shoot accurately. It is probably a good revolver to start with if shooting is your main interst. That said, I just liked the look of the Colt clones, and I don't regret my decision at all.
Doug