I really enjoyed the first two volumes of Stan & Jack stories. They really established the core X-Men concepts and introduced a great rogues gallery between Magneto, the Brotherhood of Evil Mutants, the Juggernaut and the Sentinels, among others. However, the Roy Thomas issues that followed were unbearable. The run of issues in the third Masterworks are among my least favorite across the entire Masterworks line. Almost none of the issues in vol 3 had anything to do with the X-Men, featuring throw away tales with Count Nefaria, El Tigre, the Locust, Cobalt Man (!) -- I mean these were real stinkers. I can't imagine reading these stories in the 60's and not dropping this title. No offense to Roy, who has written some great stuff and may have been under some nebulous editorial directive, but his first X-Men run wasn't it. Arnold Drake (another writer I tend to like) didn't fair much better, despite a couple of issues from Steranko and BWS. It's not until the Neal Adams issues in vol 6 (penned by Roy) that the title begins to turn north again with the Sentinels trilogy, but by that time the book was pretty much run into the ground and canceled.