Xtol stock v 1:1 v 1:2 v 1:3 and Acros 100

One of the first attractions of Xtol was its robust performance in all kinds of water. It was to be Kodaks answer to getting good development in crappy water as well as good across the globe.
Somehow Kodak must have changed the initial formula because they started blaming the failures on 'water quality'. Just the thing the developer was supposed to work through.
If it works for you, use it. No matter what others do, use it.