It just depends on you, really. I like Quilter's Newletter best because it has more articles and artsy type stuff. But if you want projects, Quiltmaker or Fons and Porter might be better (I personally am not a fan of Fons and Porter - too many projects that depend entirely on one line of fabric). Quiltmaker has some really cute projects sometimes.
I would go somewhere that has a large selection of magazines and browse through them, to see what magazine seems to have the features YOU would like. You might like McCall's. They seem to have a variety of small projects. I used to have a subscription but let it drop because I wasn't really making anything out of them, but like I said it's all a matter of personal taste.