I used UFG for many years and sometimes also with replenishment. It was mostly used, by me, for shooting the Tri-X of that time at 1250. I found the results at 1600 either with UFG or Acufine to be not as good. It was my understanding that both UFG and Acufine were phenidone based developers and that someone who worked at Bauman's (the maker of Acufine) left and started Ethol (the maker of UFG). When I started taking pictures, phenifone based developers were more appropriate for medium speed and slower films because they produced more grain with faster films. Some other phenidone based developers of that time were Clayton's P60, Ilford Microphen, Edwal FG-7 and Kodak HC-110. Over time as film stocks improved, phenidone based developers became practical for more films. Kodak's T-MAX developers were all phenidone based. There are still many choices of phenidone based developers. Ilford and Kodak make liquid and powder versions. There are nuanced differences between phenidone based developers but they are more alike than different. If I developed film more often I would probably settle on Clayton F76+ or its Arista equivalent. For now I am sitting on a large supply of metol and sodium sulfite and I can make as much D-23 as I like as often as I need to. If I feel lazy I can use a magnetic mixer with a heated base.