If you can get a Dillon 650 for that cheap, then by all means do it. That is a good deal and a progressive makes reloading pistol ammo fast and handy. But I also recommend that you get yourself a good single stage press too, to use loading ammo that you don't shoot enough of to justify buying a new setup for the 650. I load for several calibers, but the only ones I load on my older Dillon 450 are 9MM, 38/357 and 44 Mag. I also load for 380 Auto, 223, 260 Remington, 264 Mag and soon will be loading for .30-06 but don't see the need to spend $50 for each different new shell plate and powder funnel setup these calibers would need. Plus, I just feel more comfortable loading the rifle rounds on my single stage as I use a lot of long grain stick powders in them, which meter poorly and I weigh them individually.

As for reloading 9MM, once you set up for it, you can still reload for cheaper than buying new, especially if you are picky like me and don't run any of that cheap steel or aluminum crud ammo in my guns. Using Zero brand jacketed bullets I can load 115 grain FMJ ammo for around 15 cents a round. And if you don't mind polymer coated lead, you can cut another 3-4 cents a round off of that.