A question regarding value and a printing error

I was calling all the local comic book stores in search for the Uncanny X-men # 266 (gambit's first appearance). Finally, I located one and the guy says $80.00 which seems a bit cheap to me. When I ask how it looks he says its in great condition, but the printer cut the book low. He said there's no space between the word Uncanny and the top of the page, where other versions could cave 1/16-1/8 inch space before top of the page. My question is, does this "printing error" devalue the book or is he just underpriced? I'm relatively new to comic collecting so any feedback would be greatly appreciated. This is the first I've heard of this type of thing.