I bought my Dillon years ago when there were fewer choices. The 550 fits my needs as I rarely load more than 300 rounds at one time.
Never have worn out a part. Changing cartridges is pretty easy once you get the hang of things. Only thing that irritates me is that I get primers all over. This is because the cotter pin on the spent primer catcher gets bent and things don't work quite right . Minor irritation in my book.
Never have tried a LNL so I can't say. But since everything progressive is compared to a blue press that should say something.