I bought a Dillon 550 B 6 or 7 years ago. The only regret I have had was that I didn't do it sooner. I may upgrade my Dillon to a 650 or better some day, but I'll always keep the 550B since it is so simple to change calibers. Set the main match caliber on the 650 and all the others on the 550B. I'd stay with Dillon because the product support is so fantastic. I called them once with a minor issue and they sent me new parts within a couple days, no questions, no charge. That is worth something, too.