The late Keith Watson was the artist who came closest to recapturing the look of Frank Hampson's Dan Dare. Here's a brilliant cover for a 1964 edition of Eagle. A highly unusual composition that makes it one of my all-time favourite covers. Click for the giant version.
This is a less well known British comic but a worthy rival to Eagle. I think it must have been linked to the Daily Express newspaper because it featured two Westerns, The Lone Ranger and Gun Law, both of which ran in The Daily Express. There's more about the comic on Lew Stringer's blog. On the cover is Wulf The Briton painted by Ron Embleton.
Inside though, is a real surprise - Sky Masters by Jack Kirby and Wally Wood!