I have used W231/HG38 and it works. It measures well in my powder measure. I prefer AA5 for 124 grain bullets and it works pretty good with 115 grain as well. I have tried 700X powder but I don't like to have to measure each and every load. 700X is a flake powder. It isn't consistent in my powder measure. I have tried other powders with varying results.
AA5 seems to burn cleaner than W231/HG does. For a little softer shooting load AA2 works as well. There are several powders that can be used to load 9 mm ammo. It mostly depends on what is available, the bullet type and weight as well as the performance you are trying to achieve. Some powders will work better closer to the low end and some work better closer to the top end. It just depends on what you want.