Per shot and considering the fps of that shot, pellets are almost always more expensive and no real advantage if you have a supply of powder tubes.

Just load up a bunch the night before or a few before a hunt.

IMO and in my guns loose has always given me the best accuracy too. Fouling also seemed a bit worse with pellets but ive heard IMR WhiteHots are pretty clean....about the most expensive too.

Try both and see what you like and what accuracy you require.

Opinions vary