I am in the same boat as the OP. I am planning on buying a 600 f4 next summer. I am also trying to decide if the E is worth the extra money.
I came to the decision that yes it is worth buying the E but now I am on the fence. My reason for deciding to pay the price for the E over the G was because of weight and sharpness. As I get older less weight will always be welcomed. Sharper is always better especially as MP continue to climb, I see the E version as more future proof. But now being on the fence brings me to the points below.
I am questioning the new lens with a premium price tag for a few reasons.
- With the near future being mirrorless for Nikon and now Nikon has announced a 600 and 400 in a native mount for the Z series I question if it is financially smart to pay for a new 600 E when in a few years Nikon will have the Z version of a D6 along with even more updated Z6 and Z7 cameras out.
- I am also considering if I want to stay with Nikon or switch over to Canon or Sony. I am leaning more Canon with the R5 and Canon will also have native 400 and 600 coming out next year.
- If in the near future I move to a full mirrorless system do I want to be stuck with an adapter for years to come?
- Buying a 600 E or Canon/Sony anchors me into a brand and system. If I am going to make a change that is the time to do it. I can wait a bit but if by the summer of 2021 Nikon doesn't have a clear answer to the R5 and Sony A9II/A7R4 than it only makes sense to change brands.
Lot's to think about and luckily I have a little time to figure it out but I don't want to wait a couple of years for Nikon when others are already there. It also makes me wonder if Nikon would ever catch up.
Just my 2 cents.