I subscribe to Fly RC, Backyard Flyer, and Model Airplane News. Each of them occassionally has good useful articles hidden in between the ads and the typical "Greatest Plane Ever" reviews. Besides, reading piles and piles of glossy ads can even teach you something once in a while.

I enjoy reading Model Aviation every month, I think the AMA does a good job presenting balanced monthly content.

I just recently subscribed to Carsten's "Flying Models" and I think that it might be my favorite of the whole bunch. I find that Flying Models covers a nice variety of topics and focuses more on scratch-built and unique projects rather than simply reviewing the latest assembly line offerings from Hobbico and Horizon.