[Ayoh]

Have you ever tried to handhold and manual focus or only change the FL of the 120-300? I'm just guessing the answer will be "no" 

 

And while manual focusing is comparatively easy with an Art-lens (as well as the types of other manufacturers), the Fuji focus by wire system is in my eyes a clear disadvantage for long glass. Without any kind of tripod it's close to impossible to frame and focus.

 

Yes..but these lenses will obviously have auto focus..

 

Also a 200mm F2 will weigh almost a kilo less than the 120-300mm 2.8

[JJ_SO]

We're currently talking about Fuji, yes? Well, the AF is easily distracted by obstacles like twigs, leaves and other stuff - and soon I'd be too happy if the manual focus would be worth to use. But so far, each bird which doens't like me to get a picture from it, is perfectly safe as soon as he hides behind a cob web.

 

So far my experience with X-T2 and 100-400 - and that lens is not very heavy, at least lighter than that 200/2