That’s why I have both! In better times, I used the 9mm for target shooting and the 40 for concealed carry. Now I can’t find reasonably priced FMJs for either.
Getting better. https://ammoseek.com/ammo/9mm-luger shows currently touching $15/box.
For a while I was getting good prices direct from federalpremium.com — they’ve inched prices up rather than down lately.