Since my original post (#8), this thread has morphed.
Just to answer the generic "what is your favorite 38 Spl powder" question; that would be: Winchester 231 - hands down.
There are others, and from my experience . . .
Bullseye is great, but runs residuey.
AA#2 is great, but gets to leaving a grainy byproduct behind if you don't run it up a bit. Although it's fast, I think it likes a bit more pressure than most in its speed range. Even at that, it gives consistent results - even when turned down and running grainy. But overall, I think it's better suited for range level, light bullets in semi-autos (9mm, 40 S&W).
TiteGroup is good but runs too hot and needs to be under plated (rather than lead or coated) bullets. It is also really dense and so it has a very low case fill - which makes some loaders understandably nervy (not me).
N-310 and Nitro 100 is great for low-end, straight target loads. But these super fast propellants should not be run up the ladder very far - pressures could skyrocket.
Red Dot, like Bullseye, tends to run residuey. And it's just a touch slower. I have made good range shooters with it, but just haven't used it in years.
None of these above-mentioned propellants have the versatility and clean, cool burn of Winchester 231. It just works - all the way around.
I have also used intermediate propellants such as AA#5, Unique, HS-6, Green Dot, and Power Pistol. They all work; but aren't that versatile because you gotta pump 'em up under heavy bullets to get them to run properly. They work well for +P defense loads and such, but they are not what I consider workable over a broad range of 38 Special pressures.
And AA#9 with 38 Special? . . . uhh, no.