Needless to say, I came to this thread/topic as my very first stop on the REH forum. I've not looked at the posting dates (got caught up in the discussion) but I wanted to note: the Zebra version of Lost Valley of Iskander's illustrations were all "enhanced" versions of the ones that appeared in the FAX hardback edition: every one had more drawing added, sometimes quite a bit.
The FAX printing deadline caught me off guard so the work in the hardback, though fun, wasn't quite "Howard" enough for me.
When I found out Zebra was publishing the paperback (without compensation to the artist, btw) I sort of visited their offices a few blocks South of my studio and let them know the art was mine and they needed to clear permission for use through me. They immediately got onboard with that, and I told them they could have "better" art, in that I'd been finishing all the work that wasn't done for the FAX edition.
SO: if you have that Zebra paperback and not the FAX hardback, you have more and better art, with the loss of 3 fairly "thin" color plates, two fairly forgettable end papers and my less than powerful FAX dust jacket painting. You also have one b/w full-page illustration that FAX didn't include in their book: "Dogs! Jackals! Noseless Abominations!" It is tapped in as the last page of the paperback.
(I see this thread is very much alive and recent! great!)
Very cool info! You ever feel the need to illo some REH, I always got a book in the works somewhere that could use a jacket or interior work, and we'd love to have an artist of your fine caliber work on one of them, anytime