I picked one up at a local auction and then sent it in to Dillon for a cleaning / replace of worn parts. just got it back and it looks like a new machine now, they replaced over 200.00 worth of parts for the 47.95 cleaning fee....one can not beat that for service, that is for sure.
It's a great press, as long as you do your part. The RL550 uses manual indexing, this is where most douple charges occur as folks forget where they were and operate the press twice without advancing. Other than that it's a great press, Dillon's service is unparalleled.
I don't think you could have done much better. The 650 is a more advanced machine but the 550 will accept more calibers, including some really oddball stuff.
Great presses. I've had two of them and sold them when I needed money, but intend to get another one at some point...
IMHO it's not the best if you only need to put together 100 rounds of rifle ammo, or are testing loads, but great if you're in production mode and need to do several hundred rounds. If you're shooting thousands or rounds a month it's probably better to step up to the 650.