Howdy
There are several confusing terms being bandied about in this thread. Perhaps I can add a little bit of clarity.
'New Model' 'Old Model' Uberti
When the Colt Single Action Army first came out in 1873, the cylinder pin was held in place by a screw that angled up from the front of the frame. You can see the screw in this photo of an old Colt. It is at the front of the frame just under the cylinder pin. Notice how subtle the screw is, mostly buried in the frame of the gun. Colts from this era are said to have the Black Powder Frame. More about that in a little bit.
Colts from this era had what is known as a bullseye ejector rod handle. Basically the shape of a donut with a hole in the center.
The problem with the old angled screw was you needed a screwdriver to take the cylinder out of the gun for cleaning. And in the Black Powder era, you needed to clean the cylinder pretty often. So in 1892 Colt started phasing in the modern transverse, spring loaded cylinder pin latch on a few target models. By 1896 it was a standard feature.
At some point, I'm not really sure when, Colt changed the shape of the ejector rod handle to the present crescent shape.
OK. So Uberti or Taylors, or somebody is playing around with terms here. What they are calling the New Model is simply the way the Colt has been made for well over 100 years, with the spring loaded cylinder pin latch and the crescent shaped ejector rod handle. The 'Old Model' is what they are calling the guns with the Black Powder frame now. Uberti has cashed in on the appeal of the older design, mostly because of the popularity of Cowboy Action Shooting, and is building some of their replicas of the SAA with the old fashioned Black Powder Frame, with the angled screw and bullseye ejector rod handle.
But take a look at this websight again. Notice how Uberti has changed the shape of the angled screw from the original. It is now a big, ugly, knurled screw that sticks far out of the frame, nothing like the original design.
https://www.gunsamerica.com/blog/uberti-cattleman-single-action/
The reason is obvious. The screw head sticks out from the frame and is knurled so you don't need a screw driver to remove it, supposedly you can grab it with your fingers and remove it if it has not been torqued down too much. Personally, I think anybody who buys this design is kidding themselves if they think it is duplicating the old Black Powder Frame design. You can buy a replacement screw that duplicates the design of the original, but what's the point? Then you go back to needing a screwdriver to remove the cylinder. The transverse spring loaded design has been around for a long time, and it works fine and you don't need a tool to remove the cylinder pin if you want to wipe off the cylinder and the cylinder pin at the range.
But I digress.
One other thing. Shooters ask all the time if they have to shoot Black Powder only in a revolver made with the old fashioned Black Powder frame. If it is an original Colt, yes, absolutely. Colt did not warranty the Single Action Army for Smokeless Powder until 1900, several years after the modern transverse spring loaded latch appeared. But the modern replicas with the Black Powder Frame made with modern steel are perfectly fine for Smokeless Powder.
"Clicks"
What is it with guys who have to hear four clicks when they cock the hammer? Do they really think that makes the gun better? I have 1st Gen Colts and 2nd Gen Colts that have all four clicks. I have an Uberti Cattleman that has all four clicks. I have Ruger Three Screws that have four clicks. I have Rugers I have converted with half cock hammers that have three clicks. And I have Ruger New Models that only have two clicks. The only time you can hear all four clicks is when you are fondling the gun while watching an old Western on TV. At the range, if you hear all the clicks you are not paying attention to your shooting, and are cocking the hammer awfully slow.
Just my opinion of course, do with it what you will.
I cannot comment much on the newest Uberti design with the firing pin that withdraws into the hammer when the trigger is released. I first saw a video about it back last spring I think. I have not seen one yet. I doubt if I would buy one, but I don't buy many new guns these days anyways.
Here is the video I saw about the new Uberti design back in March of 2016. The discussion about the new hammer design appears about half way through.
https://www.youtube.com/watch?v=XbnlwovDTw8
Here is Uberti's blurb about the new design. Note: This video incorrectly mentions Transfer Bar technology. This design does not use a Transfer Bar in the sense that Ruger uses a Transfer Bar. It is more properly an actuator bar that shoves the firing pin forward when the trigger is pulled. When the trigger is released a spring retracts the firing pin.
https://www.youtube.com/watch?v=ecOGRmMtFow
Rugers: the 'original model' Vaquero was manufactured from 1993 until 2005. It was nothing more than the standard Blackhawk model with the top strap recontoured to the shape of a Colt and the adjustable sight removed. Had the same Transfer Bar type of action as all New Model Rugers making it completely safe to carry with six rounds under the hammer. The 'original model' Vaquero was discontinued in 2005 with the introduction of the New Vaquero. (A really dumb choice of names, what are they going to call the next one, the Newer Vaquero?) The New Vaquero is simply a scaled down version of the older model. The old Blackhawk design was larger in size than a Colt, and the older Vaquero model was the same size. The New Vaquero more closely duplicates the dimensions of the Colt. As with all Rugers, there are no leaf springs inside a New Vaquero, all have been replaced with coil springs. this also increases the part count because all the coil springs need a plunger to transfer its energy to the part is works. Other parts of the mechanism of a Ruger are radically different than the old Colt design too, particularly the way the cylinder stop is actuated. Rugers can be a handful to take apart and get back together again, but there are excellent videos on the Ruger website showing how to do it. Does a Ruger feel different than a Colt? Of course it does. But I can tell you I bought my first Blackhawk in 1975, and never felt that it was a particularly clunky gun.
Leaning toward the SmokeWagon,
Does it have the retractable firing pin ?
I'm pretty sure no, but why not call up Taylors and ask?
Also what say you? 4.75" or 5.5"
Which balances better ?
Completely subjective decision. It's up to you, you will have to handle them to decide. There were three standard barrel lengths for the SAA, 7 1/2" 5 1/2", and 4 3/4". The most popular barrel length was 5 1/2". Personally, I never much cared for the appearance of the 5 1/2" barrel, always looked boring to me. I like the extremes.
Two other things. Some of these replicas are sold with finishes they call 'charcoal blue' or various funky names. A very bright, almost robin's egg blue. It is not a robust finish, I had a Cattleman with that finish and within a year the blue had all worn off the backstrap simply from the sweat of my hand. Modern blues are much more robust.
Also, be sure what type of rear sight you are getting. Many of the modern replicas come with a narrow 'V' type rear sight, just like on the early Colts. Much more difficult to sight in than a more modern squared off rear sight.
This photo shows the squared off rear sight of a 2nd Gen Colt on the left, and the 'V' groove of an Uberti Cattleman on the right. Even though the 'V' groove is more authentic to the older designs, I find the squared off 2nd Gen rear sight much easier to use with my old eyes.