catboat, the RCBS .45 270 gr SAA is an excellent bullet. Cast of straight WW, it weighs around 285 grs.
The other bullets you list are also good. Believe it or not, one of the most accurate bullets I shoot in .45, is the Lee 255 gr RNFP. Over 8.0 grs of 231, one inch groups at 25 yds are not uncommon. I know people like to bash Lee, but for the money, a good deal. I'm still casting with Lee molds over 20 yrs. old. For less than the price of a 2 cavity, you can get a Lee 6 banger.
Over time, you'll end up with all of them
BTW, I have the 7" and 4" .45 colt Redhawks and love them. The 5 1/2" has eluded me. I opened the throats to both guns about .453". Also have numerous Blackhawks and Bisleys in this great caliber.(they too neede throat enlargening)
Elmer was right ! I've spent most my money on guns, molds, and reloading supplies, the rest I just wasted.
President and active member of the "callshot" fan club
It takes an extraordinary man to handle an ordinary day for Steve Call.