It costs more to practice than with .40 or 9mm, though.
That's very short sighted. Use the 9 or 40 if that's what you feel comfortable controlling, but, unless you have the training budget of USN SEALS or Deltas, better to focus on quality of practice.
Yes, unpredictable yet strong aikido and Colt 45 skills are wise (and fun) use of training time. Mr. Seagull was on to something here.
Some medical examiners have observed the effectiveness of a single accurate 45 vs multiple 9s.