What you need to decide first is are you interested in tradition, or functional utility most?
If it's functional utility, Ruger is the best gun for the money. Blackhawk for the greatest range of ability, New Vaquero for Colt size and look alike.
On the other hand, if you want case hardening, four clicks, the traditional half cock, and carry "five beans in the wheel" then get a Colt, or a clone.
But, beware of the Blackhawk trap. If you start with a (new model) Blackhawk in .45 Colt, with its adjustable sights, safe carry fully loaded, and the ability to match .44 Magnum with carefully worked up handloads, you might not be happy later with a Colt SAA which can't match this.
I got my first Ruger .45 Blackhawk (convertible) a 7.5" in 83. I currently have 10, Blackhawks, Super Blackhawk, Vaqueros and a new Vaquero, and of course, a Super Single Six.
ALL new model guns. I don't, and won't own a Colt, simply to have a Colt, and after all these years with Ruger new models, the different manual of arms of the Colt seems odd to me. Also, the Colt SAA (and the New Vaquero) seem "small" (and fragile) after decades with the larger Blackhawks and Vaqueros. Its a personal matter, but it is kind of a trap.
A friend of mine has Colts, a rather nice selection. To HIM, my Rugers are big and clunky, and don't "load right". TO each their own.