Not sure about the Max Cash, but I had the Hex Cash for a short period of time (returned them once I got my Night Falls).
As for those, I ended up getting a size 28, and I'm normally a 27 or 28 in Diesel (27 in stretch washes, 28 in 100% cotton) and a 28 in Diors (19cm, 17.5cm). They fit pretty well, and I think they would have stretched out perfectly.
Hope that helps.