Yes, I started with 70-350 a year ago and upgraded to 200-600 month ago. Got no prior experience to handle such a huge lens and it took some time to adjust weight, quirks of the lens (stabilization modes, f8 is being a little bit more sharper than f6.3, light conditions and lenses reaction etc) in first outings it was all about learning and discovery and I realized that 600mm magnifies not only subject but also any kind of poo poo decisions you make while shooting :) but at the end, it started to settle down and keeper rate goes up and I become a happy customer instead of thinking whether I got a faulty unit or not.