You will be pleased with the Dillon 550. It appears that you are a fairly experienced reloader, so the only advice I can give at this time is you will develop a "feel" for the Dillon, and if it doesn't feel right... STOP!!!
Dillon makes it easy to stop and restart with their brass buttons being removeable to remove a case from a station.
The Dillon dies are great for pistol, the large radius makes it easy for the case to find it's way into the sizer, even if it doesn't start out straight. This radius does not allow you to size as far down as some other brands, but there is a simple solution for that, the Lee carbide factory crimp die in station 4.
https://leeprecision.com/reloading-dies/hand-gun-dies/lee-carbide-factory-crimp-die/
I use this on my dillons for my 9mm, 45 and 40S&W. I do not use the crimper at this station, but the carbide rim resizes the case to insure no wrinkles, or bulges. I started using this for IDPA matches, so I didn't produce a round that would not chamber.