I use it in .357 and .41 Magnum. It's a very fine grained spherical that meters exceptionally well, burns cleaner with less muzzle blast compared to H110/W296 or 2400. I get very good accuracy with it as well. You can find .454 load data at: Ramshot
True Blue is an excellent powder and you can use it to get medium to near magnum velocity in the .357 and the .454 Casull. It also works well for 9mm, .40 S&W and .45 ACP. As you've probably noticed, the Ramshot data for .357 Magnum only goes up to 35,000 PSI. If you want more powerful data try the Lyman Pistol & Revolver III or the 49th edition load manual.
I have been using Enforcer for .44 mag and .357 mag, I like the fact you don't need magnum primers!! I've noticed lately that my Desert Eagle (.44mag) has been firing a lot of excess powder (lit the local indoor range on fire twice!) so I'm reducing the powder amount(using 22gr with a Nosler 240gr JHP) in stages since the Deagle requires a relatively hot load to cycle it properly....I guess the best thing to tell you is you need to customize everything for the gun you re shooting!!!
I'm going to try H110 and large pistol mag primers next time I reload for it just to see if it makes any difference in how much powder burns off!
All part of the reloading fun!!
I've tried H110, AA#9 and True Blue in my 454s. I was trying to ignite them with a CCI 450 primer and have been having all kinds of trouble. I tried a starting load of True Blue and the 450 plus 250 XTPs and had to practicaly hammer the brass out of them. I don't like AA#9 either but it could be because of the 450 primers. So far I've only found H110 that seems to be consistant. I would be interested in knowing how Enforcer works in your 454. I don't know if it was a bad batch of primers or if it's just the CCI 450 but they have been nothing but trouble and I won't use them ever again. So far Federal 205 and WW small rifle primers have fired each time.