I have one and am satisfied with it. I really like the quick change die feature but the cost of extra inserts is one of the drawbacks too. I typically load one particular bullet/powder for an individual caliber so being able to pop the one set of dies out and replace them with another and continue loading is a nice feature. I often use my "need to reload a few rounds" to get out of "Honey Do's" from the wife and found the time needed to switch dies was long enough to notice and figure I was done. For my most frequently loaded rounds I also have dedicated powder measures so I spend hardly any time setting them up either. Dillon seemed the most onerous between them, RCBS, and Hornady in my limited experience.
My second biggest gripe was with the primer tubes, no one carried them locally and I had to get extras from Hornady for MSRP. RCBS and Dillon have local distributors that I can purchase these from but Hornady does not. I can get anything else for the machine, just not primer tubes.
I was torn between the L-N-L, Dillon 550, and RCBS unit but went with the Hornady as it was the less expensive at the time. Dillon's customer service and support is second to none but I did not care for the powder meter. RCBS lost me with their priming system using those strips while Hornady's use of the inserts were a concern as I did not know if they would become loose in the machine or not. So far, so good and I have put quite a few rounds through the machine. I don;t think it matters much what press you get as long as it is of quality and you can live with the quirks.