i do own 2 sigma 200-500/2.8 - one canon mount, one nikon mount. did do some test shoots "canon girl vs nikon girl" a while ago, but never did release it anywhere. i'm located nearby frankfurt/germany, if somebody wants to use or test them, just email me to email@example.com
I live in Kaiserslautern when I'm on my six-weeks off from work as a helicopter pilot.
Since you offered, can I borrow your Canon version for my next six-weeks at work. It won't go far... I work in nearby Nigeria. Very secure there.. no crime or thefts!
I'll get it back to you in 45 days....maybe. Thanks for the free offer!!!