I shoot a pair that are chambered in 44 Colt. I have tried Black Hills ammo of the smokeless variety. It was good stuff. I picked it up at a state match from a vendor. No special price, I just wanted to try some factory ammo cause I was wrestling with light primer strikes and pierced primers. I got that fixed up. Anyway, the opentop have a very natural point for me and are easy to shoot one handed.
For most ammo, I reload, and shoot black powder.
The only problem I am dealing with now is the brass I am using is a bit hard. So I get a considerable amount of blowback. I have reloaded cartridges to test when I can get to the range. I opted not to resize, so I am going to see how bad the blow back is using fireformed brass. If that is a problem I will try anealing about 100 pieces of 44 Colt brass to soften the neck up.