For what it's worth, Unique was reformulated a few years ago to make it burn cleaner. This happened about the time they switched from the cardboard containers to the plastic bottles There seems to be ongoing disagreement about whether or not the older load data needed to change as a result of the new formulation.
Personally, I use Unique a heck of a lot. It is very versatile, and can be used in just about any handgun caliber. However, it would not be my first choice for a hotter load in any caliber. I can't specifically comment on 45 colt because it is the one caliber that I only load with BP, but in other pistol calibers I would be looking for a slower burning powder to get maximum velocity with minimum peak pressure.
My first look for maximum velocity loads would be for data involving H110 or IMR 4227. Some people are partial to WW296 instead of H110, but that might be a Chevy verses Ford thing. Be careful that the load data is not mean specifically for Ruger's or TC Contenders or Rifles Only.
One the flip side, for CAS shooting, target shooting and plinking Unique is an awesome choice for the 45 Colt. It is the powder they used at the beginning of time in them. For lighter loads it is great. It has a wide tolerance for not filling the case. When one backs it down too far, ignition will get a bit erratic. At that point in time, go up a half grain or so and it is usually fine. I personally use only Magnum powder with the lighter loads of Unique, as it allows one to get consistent ignition when working on the edge of too light a load.
Trying different things is fun ;-)