Neck Turning is needed in my opionion for tight bores, and for my 300RUM. I had such trouble getting good remington brass, I had to neck turn. But for 308's and such, I usually can cull to find good brass.

I have the neck turning tools for 7mm and 308, and rarely do it anymore. Its better to cull the brass. Or better yet, just load and sort out good bullet runout and back bullet runout. Use the bad (>.004") for fouling and such, and good for long shots and hunting.