Hi renaissnce7697 and a big Texas Howdy to ya. Welcome to TFF.
Well, I have used National for some time and found them to be a super hard cast bullet. Never had a leading problem with them. If I recymember them right, they are about a 18 in Brinell hardness.
Lookin over at Sureshot, they state that theirs is 15 Brinnel so they are a little softer. It may or may not make a difference to you, as it depends on how fast you want to push them out the barrel as to if it will lead the barrel or not.
Anyway, the hardness and lube will be the main differences.
Anyway you choose, keep 'em in the black and happy shootin'