Reddit mentions of Schubert: Piano Works: Sonatas / Moments Musicaux / Impromptus / 'Wanderer' Fantasia

As with all box sets, there are strong points and weak points, but if I had to recommend a single Schubert box set, it'd be Wilhelm Kempff. Kempff was one of the first (maybe the first? not sure) to record the complete Schubert piano sonatas and did a lot to bring them into the core repertoire. The entire set is of a very high musical quality, with no glaring weaknesses and a great musicality that is typical of Kempff.

Sets that I have listened to and chose Kempff over:

Uchida
Lupu
Schiff

Another good option to consider is this Brendel set: http://www.amazon.com/Schubert-Musicaux-Impromptus-Wanderer-Fantasia/dp/B0042LJTQO/ref=sr_1_1?s=music&ie=UTF8&qid=1344243350&sr=1-1&keywords=schubert+brendel+box

Though not the complete piano sonatas, it also includes some of Schubert's most popular other piano solo works, and all of the readings are fantastic.

If you ever find yourself enamored with Schubert's sonatas, I suggest looking to Richter as the first stop for supplementing your collection with individual sonatas. His D960 is superb.

• Janowski's Ring Cycle - The version I'm referring to is the 1980-83 studio version. Virtually perfect sound quality owing to the fact that it is a studio recording. There's really no particular part that stands out, it's just an incredible recording in general. Sample
  
  
• Karajan Bruckner 9 Symphonies - The version I'm referring to is the box set that was released by DG. It has all of Bruckner's symphonies and is my favorite collection. Again, they're all nearly perfect.
  
  
• Bernstein Mahler 9 Symphonies - Bernstein actually recorded two cycles of Mahler symphonies, although I don't think he finished them all the second time. Either cycle is great, but the first is classic.
  
  
• Backhaus Beethoven Piano Concertos with Hans Schmidt-Isserstedt conducting - They're all amazing but I love the 5th concerto.
  
  
• Brendel Beethoven Sonatas Recorded 1970's - A lot of Beethoven interpreters are either really mechanical or overly dramatic. I find Brendel to be great because of his traditional classical approach, while still having a sentimental tone. I believe it is this version. This set is far superior to the 1990's version in my opinion. He also did this Schubert set which I highly recommend as well.