I have done alot of comparisons with runout. I love redding comp seaters. But they are expensive. But here's the deal. If you neck thickness varies or neck runout before seating, it doesn't matter what seater you use, its going to have runout.

I like to keep my bullet runout below .004". I notice in cartidges that have freebore, it does make a difference. But calibers like a 308 win that you load close to the rifling, I can't see much difference in hunting rifles.