Thanks for the replies. The rifle I use these rounds in is an AR15, so based on your advice I will go with FL sizing. I'm just getting started in reloading and gathering as much information as I can. I was mainly looking at neck sizing as a way to extend the life of my brass.

The Lee advertising makes it sound like you can get away with neck sizing as long as you are firing the rounds in the same rifle every time even if it's an auto loader, but I thought that sounded too good to be true, which is why I asked the question here.

Could you tell me what method you use? It seems there are differing opinions on the best way to do this. Does this guy's method make sense? It seems simple enough.