I won't argue the points about Lil' Gun,, because I never used enough of it to have any direct damage. It is because a few other folks whom & respect warned me,, and I'd prefer to NOT be the one who uses it & suffer damage to my revolvers.
Besides,, I have enough 2400 AND the excellent loads it has produced for me,, so why take chances?
I've often sad & truly believe that each firearm is a machine unto itself. And when it comes to loads,, each gun has "preferences" to give top performance. In my humble opinion, that means it loads well, stays within the safe load limits, and produces the best accuracy with the chosen bullet. And a bonus is when you can use different types or weights of bullets with the same powder, and keep that top level performance.
In my nearly 50 years of handloading,, I've settled into using Unique, HS-6, 2400, 4227, for the majority of my handgun ammo. But I also have Bullseye, H110, TrailBoss, Longshot, TiteGroup, that are used in some loads. I also have a shelf full of other powders that I purchased to test in various guns/calibers,, but they didn't quite perform as I hoped. But I tried them.
And when I get a new gun, and start loading ammo for it,, I first try some of my "tried & true" loads,, to see how it likes them. Sometimes I discover they really like the same load,, and other times,, not so much. When they don't I go to experimenting.
In short,, I let the target be the final arbitrator of what works the best. Quite often,, it's loads that are not "top tier" in velocity that balance the best & give me the best accuracy.
And to quote a gun writer,, (I think it was Townsen Whelen) "Only accurate guns are interesting!
I hunt with handguns. I shoot competition with handguns. I want the most accurate ammo I can build for that gun, so that if I screw up,, I can't blame the ammo.
Just a few years back,, David Bradshaw & Lee Martin developed a cast bullet just for the .357 Maximum. They tested it extensively prior to telling folks about it. Once I got my mold, and cast my own bullets,, I studied David's test results. But I still used my same methods of testing MY gun using different powders & loads & did not automatically trust his load to be the best in my gun. In fact,, I truly tried to build a more accurate load. Yet,, all that shooting just proved that his load was the best in MY gun,, as well as his gun. But at least I had done my own testing, and my results were the same as his.
So it became the load I use in my Maxi.
If I were to get another Maxi,, I'd check it with the same load,, but I'd also try & see if I could get a little better performance with other loads.
Each gun is a machine unto itself.
So,, everybody has their own preferences in powders, primers, calibers & even the parameters of performance. It's great to have so many choices to test & use.