I presume you've started hitting the gym already or have a couple of Sherpas at hand? The lens is awesome but it kills you with its weight if you need to shoot handheld
Why not get the 500 / 600mm f.4?
I can always spend some money on monopod
I shoot indoor alot, therefore, f2.8 is more important to me than lenght. I can always add x1.4 or x2 TC if needed.
shooting 400mm indoors a lot?
Maybe I'm missing something.
1DX, 5D3, 600D, RX100
16-35L, 24-70L II, 70-200L II, 100-400L II, 50L, 85L II, 135L, 17TSE, 24TSE, 40, 100 macro, 18-55 II, 55-250 II, 1.4x III, 2x III, 600RT x 4
When it comes to gear, it is better to vote with your wallet. Bitching on online forums like a lunatic doesn't get you anywhere!