Well, CamelPilot, I won't mention my current magazine, nor the one I used to edit...
Having read it, off and on, since the first issue, I would certainly recommend Aeroplane (they've dropped the 'Monthly' bit from the title) because it is accurate almost to the point of being definitive, has a high standard of English and is very well designed.
Worth reading - although infamous for its poor repro and quirky layout - is that wonderful U.S. publication (pretty much an institution) WWI Aero. If early and pioneering aircraft are your bag, this is one you cannot miss. Subscribe now, and help keep dear old Leo Opdyke afloat!
Of course, there are many others out there that deserve praise: thankfully even the wobbliest issues of the most indifferent flying publications never sink to anything near the standard of the average C5 TV documentary!