Munkelzahn said:
Direct image link:
https://68.media.tumblr.com/8ad1cd85f5095d31600eabccd23e1a30/tumblr_oclfqmSkxu1vbxsy5o1_500h.jpg

That's strange, it seems as though the 'h' signifies that only height is restricted to 500 pixels, while the width can be whatever (presumably up to maximum).

While that is an interesting observation, it is still clear that the raw version (1920 x 623) is higher quality. All this changes, as you say, is the raw version redirection plugins that people use, as the extra character ('h') must be removed. I'll see if I can edit the current script to address this issue myself.

EDIT: I made a hotfix for the script, it's pretty simple, you can grab it here. I'll also let the original author know so they can make a proper update.