I've used ADG, Nosler, Rem & Bertram.
I listed them in the order of my preference.
With the ADG I don't have to form it to .338 so that's a plus.
It's very consistent in OAL and base to datum line.
The only negative I've found with ADG is the necks are a little thinner than Nosler and all I've seen seem to have a thick side.
I recommend turning them.
Hope this helps.
Sorry I was talking about 338 Edge brass but have seen exact same results with the RUM