Though I have yet to work with one the I would take a Krag before an -03 and an 03-A3 before an -03. I did have a nice Remington 2 groove 03-A3 that was a tack driver with 180 gr. cast bullet....that I forget what it was or the powder charge.
Don't overlook some of the European (German) cartridges in a Mauser bolt. The 8.15 X 46R is a fun, accurate and fairly available cartridge in a lot of different actions. It's also miserly on powder, having nearly the same ballistics as the 32-40. The various cartridges based on the Mauser A base and 47R case length are usually good cast bullet shooters also.
