This is a terrific box of all Mozart's String Quartets plus Eine Kleine Nachtmusik, the Bach fugues which Mozart arranged and two of Mozart's Adagios and Fugues. It's a collection of superb music, excellently played by one of the world's leading string quartets.
In my view, some of Mozart's finest music is here. I have to say that although the earlier quartets have a great deal of charm and it's good to have them, I do find they pale beside the great later quartets, which I think are works of true genius. In particular, the set he dedicated to Haydn and the Prussian Quartets are works of real depth and innovation and are they immensely pleasurable to listen to. I have a number of recordings, including Quatuor Mosaiques, Quartetto Italiano and the Amadeus Quartet, and I think these renditions by the Hagens stand very well beside those other great recordings.
The Hagen Quartet are superb musicians with excellent technique and flawless intonation. Their use of vibrato is restrained and, I think, ideal for this repertoire. Similarly, their phrasing and careful use of rubato shapes the music perfectly so that Mozart's wonderful structures shine through and aren't obscured by over-expressive gestures. There is often an audible twinkle and zest in their playing but they generate genuine passion and emotion, too (K421 is something quite special, I think). I would characterise this set as perhaps a little less austere than Quartetto Italiano, and a little cheerier and more vigorous than Quatuor Mosaiques. I love all three sets in their different ways and which is best for you will depend on your personal taste.
For a complete set of Mozart's String Quartets I really don't think you can go wrong with this box. They are beautifully played and excellently recorded, and the extras are a real pleasure, too. Even if, like me, you have a number of recordings already I'd say this is well worth getting; it has a fresh and very enjoyable feel and offers some new insights, too, and at this price for 7 CDs it's an absolute steal. Very warmly recommended.