Borrowed a 550 from a friend of mine to load some ammo I normally don't load much of. Needed to load a small lot for the gun show this weekend. I could grow to like this, but my chair has wheels. Every time I push forward to prime the case, my chair rolls backward away from the bench. I have to scoot myself back in position every time. Going from standing with a 1050 to sitting with a 550 (no strong mount) is quite the experience. I can't believe how slow the 550 is compared to the 1050.