I mainly use SR4759 in black powder rifles like my Kropatschek, my marlin 1895 carbine in 38-56 and 71/84 Mauser.
It duplicates black powder pressures very well in all 3 of those. Too bad I can't get more as it is irreplaceable in those cartridges.
4227 works well in many the cartridges I've use it in but I find I need to use a dacron filler to get reliable ignition. I tried it in 7.52x54r last year and couldn't get it to group well though..
My go tos are red dot, 4198 and 2400.
I like 2400 the best at 18 to 20 grains and accuracy is very good. I've yet to load it in any cartridge and not have useable accuracy right off the bat.
My 1903 Springfield eats a steady diet .311 180 grain cast bullets with medium charge of 4198 powder. Moa groups have been the norm with that combo.
My k31 shoots poorly with red dot and 4198, but 2400 gives me consistent accuracy even at 200 yards.
The main reasons I load cast is its cheap, bore wear is zero, and I can make my own bullets from scrap. Also shooting cast will make any of your bad habits very apparent. If you don't have a good trigger control, or your follow through isnt up to snuff the group will suffer.
During the powder shortage I really didn't mind as 1 pound of powder will get a lot of shooting done if you are loading cast.