If you don't plan on changing calibers much, and if you do, only pistol calibers, then get a Square Deal B. Even though I have die sets for 9mm, 10mm and .38 Special, mine is semi-permanently set up for 9mm.
It's cheaper than a 550 and it indexes automatically. Negative? Again, pistol-only using proprietary dies.
According to Dillon, it cranks about 400-500 rounds an hour.