Unique's modern clean-burning easy-metering alternative = Hodgdon Universal Clays.
Reeeeal close to Unique in burn rate; real close.
Or, Alliant Power Pistol, Vihtavuori 3N37, Accurate AA5.
While I still keep a jug of Unique around, I burn buckets of Universal Clays, most specifically in revolver chamberings.
I am NOT stuck on one powder; I use twenty.
"all my ammo is mostly retired factory ammo"