I have a 650. At one time I had two, one set for lg primers, and the other set for small. If you don't get the case feeder with it, you might as well save some money and get the 550. The 550 is a good machine that will be hard to outgrow. Its hard to beat the RCBS Rockchucker to start with! Iv got 4 presses mounted on the bench. A Rockchucker, an RCBS "Big Max", a very heavy press for case forming, A Star, and the 650. The rockchucker gets used the most. Respectfully Terry