I've been using and enjoying a Dillon 550B for about 25 years. Works great, does all I need. Yes, Dillon service is ledgendary... as good as it gets.
I seem to load 1000 rounds a mouth or so... sometimes more. And as odd as it may sound, I wouldn't WANT the machine to go faster. Reloading is kind of a relaxing time for me and something I look forward to. There have been many times that I would poke around looking for SOME cases (ANY cases!) to fill... just for the quiet rhythm of reloading.
Have you ever talked to anyone with a 550B who REGRETS having bought it? I don't believe I ever have.
best,
StrikeEagle