Well I do not buy posters because they are popular (have the correct re-sale audience) or have the correct size.
I just buy what I like.
And true the 1976 king kong I wouldn't buy either, not even for 50 bucks because IMO it's poor artwork.
But I do not dare to speak for others, will be other opinions and likings out there.
Problem is that to many people are into "collecting anything " to gain some (easy) money , and that's a pity.
As for the:I count already one .
So I guess I can no proudly wear my " my momma says I'm special" t-shirt. 
Maybe I should start a poll on this. 
Would you pay 100$ for this mint VK 24 sheet?
Yes or no.
poor artwork?? Wow.. The poster art by Steve Berkey is maybe the best thing about the movie. The art on all the posters is excellent work, by a top-notch illustrator
would I pay $100 for the Knievel?
No chance. I doubt many on this list would and as I said, you need to find a "special buyer" if one exists.
Someone who is buying it for a museum or exhibit. Seeing as the only Evel Knievel Museum to exist is nothing more than a room inside an office on the east side of town here in Vegas, where he has maybe his biggest connections... well, I think that exhibits what little regard there is for him today.
No trying to dog your poster, but there is a reality about this material.
Not all posters are special by any measure and lots of things I think are or should be sell for less than $20 every day in this hobby.
You're looking for a one-in-a-million buyer.
It's cool, but cool isn't the criteria for money in this hobby very often
