Karl-
Good question and one that has been bantered about either in another thread on this site or on the now defunct TDT.net site.
You will get collectors that will say PC copies are worth more and others say worth less. I think it boils down to a personal preference/belief. For instance, take the S/L Gunslinger. There were 52 Lettereds, 500 numbered S/L and just 12 PC copies (also, some Authors copies etc.). Does a limitation of 12 make it more valuable and collectible? There could only be 12 complete PC DT sets versus 500 numbered ones. In this specific case, I think a PC copy of The Gunslinger is worth modestly more than a numbered copy. But for a PC copy of say From a Buick 8 versus a numbered copy....PC holds no additional appeal at all for me, and, in fact, holds slightly less appeal. In the case of From a Buick 8 (and others like it), to me a PC copy feels like you "missed out" getting in on the book when it was first announced and orders taken. A PC copy means you were late to the game and you were able to score an "extra" copy from the publisher. In general, I feel that way about most PC copies (except those of the Dark Tower books), but that is my opinion. I am sure someone else here can make a credible argument as to why they are preferred to that person. Sorry, but I think there is no clear cut answer...it is a personal preference in the end.