I'm trying to not do the naive pdf creation, where each page is just the raster. Trying to keep the JBIG2 bilevel, as I get better quality at lower file size. Using jpeg2000 too, where appropriate, but the pdfs are still x2.5 the size of the original. Though, I can have it spit out decrypted djvu files that are exactly the same filesize... I just don't like that format for archival.
If you want the Rolling Stone or Playboy archives decrypted, ReconSuave on github has tools to do those. I got tired of waiting for him to do The New Yorker though.