how important is it, really, what kind of hull you use?

i have a box of mixed hulls (trap range pick-ups) all are low brass. most are frderal, some remington, and some "other", i really dont plan on separating them. all the reload data seems to be quite different from one hull to another, with a lot of them not even listed for the same powder/wad combos.

is there really so much difference from one hull to another to make this matter??