Some of Asgard is pretty decent. Other bits, like the fiction & reviews, seem rather out of place, and stuff I certainly wouldn't want to print out, so shouldn't be in a pdf magazine...
I've been looking for the first issue of Campaign magazine but I've never been able to find it. I will also look for their 2nd issue. I was thinking about trying that Gaming Frontiers magazine, but it seems to have an awful lot of fiction and is quite expensive, so I passed. I
I subscribed to Dragon last year, but let it lapse. After a few good issues, it quickly became pretty much just an ad vehicle for WOTC's products - FR, Chainmail, and the splatbook of the month (or WOT d20). I also love how they try to cram in a historical setting into 2 pages, yet devote 3-4 pages to letters. Yargh - why would anyone want to read letters in a magazine you buy? Not to mention the lousy fiction, which is typically completly unrelated to gaming, and are just really bad short stories.
Dungeon is remarkably good. Most of the adventures are fairly generic, and when Polyhedron isn't rewriting gaming history by screwing up past settings, the mini-games in it are a good deal as well. They also offer tips on scaling the adventures, which is nice.