I have mostly Hornady brass but also federal. Never tried starline so I cant comment on them.
Either way, Hornady or Federal, for me, it's totally random when the brass goes bad. And by bad I mean the primer pockets are to loose. I have yet to have to trim any brass, but usually between the 3-5th reload, the primer pockets let go.
On the valkyrie facebook page, I was able to get in on the primer pocket tool, just waiting on receiving it. Mostly because I'm sitting on about 250-300 "bad" brass, all with the primer pockets that are to loose. I was doing the acorn nut and hammer trick, but since it's now summer time in Phoenix, I dont shoot.