So I know I've said time and again I'm not really a comics guy... but the comic books were basically the last big hole in my collection, so the other day I caved and ordered this (as well as putting in a pre-order for the second volume).
Forgetting the Greg Land tracing clusterf**k for a moment, I feel like Marvel have otherwise done a bloody good job of this. Collecting the obscure bits and pieces that Dark Horse always forgot about is what sold me. Stuff like the oft-requested Countdown, and the Kenner comics - even if they are totally daft and childish, how great is it that Marvel actually went to the effort of including them for the sake of completeness? Even the Alien 3 trading card comic is in there.
Here's hoping Marvel's subsequent volumes will be equally comprehensive. (Judging by the fact they're apparently including the incomplete Crusade in volume 2, they will be.)