While I don't own a USFA Single action I thought that I would reply since no else did.
Awhile back I was looking to get a single action just because and it came to a colt single action army, a USFA, and a ruger old model vaquero.
I found the trigger of the USFA to be better than the colt and the ruger. The fit and finish on the gun was at least equalt to the colt, imnho I think it was a little better. The dealer and a customer both told me to go with the USFA if I really didn't care about the colt name. They had a list of reasons that they prefferd it to over the colt. Honestly in my hands with my eyes closed it felt like it was better made, had a better trigger pull, and a smoother hammer. YMMV.
That being said, I went with the old style vaquero. I wanted to take the pistol to the woods with me and I wanted to be able to use Buffalo Bore ammo. So I went with the ruger.
Good luck with your choice