Oh man, you guys haven't lived until you've heard Joyce Hatto's rendition!

I have several versions--Horszowski, Fischer, Gould, Feinberg, Kirkpatrick, Walcha, and snippets of S. Richter (need to buy the whole set one of these days). Here's a mini-review (FWIW)
On the whole, if forced to pick one set, I like
Edwin Fischer's version the best. His interpretations are a bit romantic, as one would expect from the age (recorded in the 30s), but he seems to have a better intuitive feel for these pieces than anyone else I've heard. Everything seems to fall into place perfectly, and you (at least I) end up thinking, "THAT'S how it is meant to be played!" Purists and HIP fans will disagree, but I challenge them to listen to these recordings attentively and with an open mind for at least a couple of hours.
Gould's are hit and miss. Some are sublime; at his best, he can bring out the counterpoint and rhythmic swing of these pieces better than just about anyone, but at worst they are quite harsh, gritty, and perfunctory sounding, at least to my ears.
Horszowski's are very nicely played, if a little dull (I believe he only recorded Book I).
Feinberg (I have the Classic Records set) is very interesting, and really very romantic--overly romantic in some cases for my tastes--even more so than Fischer's renditions on the whole. Given that these were recorded in the 1950s, this type of interpretation is really more than a bit anachronistic, as is the sound quality (not as good as most other 1950s recordings), which has its quirks, especially irregularities in volume (you may find yourself with your hand on the volume control more often than you'd like). Still, his tone is lovely and his feeling for the music is obviously very deep.
Kirkpatrick and
Walcha (both on harpsichord or clavichord) are very nice sets and both very beautifully played with slightly slow tempos throughout (especially the Walcha). I think I'd favor the Walcha just a bit, if only for the great beauty of the recorded sound (I have a 5 LP set on EMI/Odeon)