I woudl say 40 and 44 are fairly evenly matched performance wise.
Ex-Westside 8 , like 12 is a monster she is very powerful but she is also very slow but coudl do the same work as 12. She was not a new engine when she arrived at the loop and was retired becasue of the need for some fairly substancial boiler and runningear work. She is still servacable after the needed TLC and I hope one day she get it.
15 was able to handle 4 maybe 5 cars I think. I never saw her in passenger service , only as a switch engine.