$25 for a 24 X 36 poster, signed individually and personally and no logos or whatsoever, just the photo?
Sounds like a sick deal to me, all the kids saying its too much probably aren't the market he'd want anyways because they have no appreciation for good, quality work. For them it's the same as any other poster, but for Felix its making his great photography work available to the general public in a easy, accessible and affordable way. Think of it as something you could even have up on your wall framed, and it would look amazing because its just the photo and the signature.
Printing a 24 X 36 isn't cheap either; he's already giving us a great price; so why are people bitching about it, its $25! You could make that much mowing someone's lawn for 2 hours.
Go for it dude, I think it's a sick idea.