[davidmanze]

The sports version has it's strengths in being robust, weather sealed, dust sealed. And bloody heavy. Without tripod it's challenging to hand-hold it. Are you sure you need a zoom? I've no idea how fast it will AF, but what I saw from other Canon lenses in front of Sony cameras, I wouldn't be afraid - even if it's bit slower, what good is speed for if AF is typically phase detection limited and although possibly faster, less precise?

 

Buying a lens now and the adapter much later means, you have to wait possibly for quite a while - the difference between Sigma's introduction dates and delivery dates can be considerably long. I waited 8 months form introduction to delivery of the Sports version.

  Most Canon lenses I have seen on mirror-less using adapters are F2.8...70-200mm.... not "F5-6.3" 150-600mm.... that's a massive difference!...... I have nothing against the principle per se.........and it's not just a question of speed... if it hunts back and forth taking a few seconds and maybe not locking on .........then what?

 

     More info from others users must be sought, or otherwise try renting  them out........the project is only viable if it works!  

 

    Perhaps JoJu you could try out your Sigma sports on the Fuji to see if it's a goer!