When I was looking for some new powders to try I picked up some Hodgdon Longshot, IMR 800-X, Alliant Red Dot, and Ramshot True Blue.
Hodgdon doesn't list Longshot data for .38spl, .380, nor standard pressure .45LC but they have some very respectable data for the other calibers you listed. I've found it works very well in 9mm and .45acp, seems to work best with mid-upper charge weights in both calibers. I'll be using it soon for some .357 and possibly .40 but I've yet to use it with those to date. It's a flake/flattened ball powder, a good bit smaller than Unique. On rare occasions I'll get a .2gr variance up or down with it but 98% of the time it's within .1gr of my target charge weight, about as consistent as you can ask for from a powder measure.
True Blue has data for every caliber you listed with the exception of standard pressure .38spl but there is +p data for .38spl. So far I love this powder in .45acp. I'd say its only 2nd to Unique in that caliber for me. It seems to work better with close to MAX charge weights in .45ACP. It's done well in 9mm for me. And was quite good in 5.7x28, where its typically the most suggested powder for that caliber. It's a fine ball powder and meters with extreme consistency from Hornady powder measures.
I hate 800-X. I've found nothing so far that meters worse than this powder. Even long cut stick powders meter more consistently for me. But if you weigh out individual charges it does work quite well in .45acp. But because of the metering issues I haven't used it since my first tests. If I knew anyone that loaded for shotguns I'd give it away as its supposed to be excellent for that. Many say Unique doesn't meter well but with Unique I find that .2-.3gr variances don't matter on the target. I do not find the same to be true with 800-X.
When I first tried Red Dot I was using it for .45ACP. It did pretty good for plinking loads but W231, Bullseye, and Unique all worked better for that purpose. But I was very pleasantly surprised when I tried it in .38spl. 3.3gr under a 158gr Missouri Bullet SWC, any SPP, and a light roll crimp seated to 1.45"(?, I'd have to check my notes to be 100% on OAL). That's is a very light recoiling load with superb accuracy. It does tend to be a somewhat dirty load but for how well it shoots I'll never complain about it. If I remember correctly its a flake/flattened ball powder with the flakes being just a little bigger than W231 but smaller than Unique. It meters nicely and has pinkish-red "marker" flakes.
