Uniflow for over 20 years and it is working as well as the day I bought it. REDDING if you want a competition grade powder measure and the price increase that will entail.
I have never had an issue with any powder through the Uniflow, but I have also never used IMR 800X. Blue Dot will meter about as good as you can expect it to with occasional flake cutting and I don't believe there is a way around that unless you want to give up precision. My charge weights are very consistent with Blue Dot and I'm not going to buy 800-X just because it is the worst case scenario and toughest test for powder measures with handgun charges. Rifle ball powders of course work very well and for faster ones like W-748, small charges can be dropped accurately with the small drum as Jim Watson pointed out. Extruded Rifle with the large drum.
I like the the changeable setting feature of the new Hornady and I could live with the Lyman 55. The Uniflow is the standard by which all powder measures are judged!