If you are going for the most powerful loads, then there are some ball powders that can give you higher velocities than flake powders. For example, WW-296/H-110 and 300MP should give you higher velocities at max allowable pressures than you can get from 2400 in your mag revolvers.
I don't know what was meant by what you heard about ball powders being hard on a gun, but I can guess: some max loads with ball powders, especially with light bullets, give a longer duration of high temperature gas at the cylinder gap and forcing cone of a revolver. That has proven to erode forcing cones and cut grooves in top straps above cylinder gaps on some magnum pistols. Lil'Gun became notorious for that, especially in the .357 Maximum, and in the .357 Magnum with 125 grain or lighter bullets.
Some slow-buring ball pistol powders (e.g., WW-296/H-110) have a narrow range of pressure between squibbing and max allowable pressure, so those need to be used as full-house loads or not at all. But, using a lot of powerful loads can erode the forcing cone and even crack it, especially with light-for-caliber bullets. So, although you could probably do the same thing with max loads of 2400, you can also take more off those max loads with 2400 and still have plenty powerful loads that are somewhat easier on the gun.
That said, I do use WW-296, but not Lil'Gun for my magnum revolvers. But, most of my shooting is done with mild magnum/hot special level loads using powders like Unique and Power Pistol. I use Bullseye and Clays (flakes powders) for target loads, and see no reason why WW-231/HP-38 (fast-burning ball powders that can be loaded to low pressures) would be any more damaging.