I use a lot of WST for the lower pressure rounds , 38spl, 45acp . I use WSF for all my midrange loads in 357 , 41,44 magnums . Blue dot gets a lot of use in 45 Colt and 41 , 44 magnum . It gives me all the power I want or need in the larger calibers . Blue dot is supposedly temperature sensitive . When it's that cold I find something else to do . If I want a full magnum powder , Ramshot Enforcer / Accurate Arms 4100 works well . I changed to those when Alliant 2400 become non existent . But if only one powder ---WSF would be my one choice . Many will say " Unique " . I personally have never been one to follow the crowd .
Bullet weights ? for 38spl / 357 mag - 158gr and the Keith 173gr swc . 41 mag--220 gr Keith swc, 44 mag-245gr Keith swc , 45 Colt- 255 Keith swc or the Lee 255 RNFP. I cast all these myself . The 38/357 bullet used most is the Lyman design 358156 w/o gas chk and then the Keith swc .