I'm not sure I see a point in trying to decide who has the best complete (or, mostly complete) set. The pieces are so varied I think you would have to approach them etude by etude. For instance, I think Lewenthal's Symphonie and Le festin d'Esope are the best, but obviously he didn't record the others, so to view it in that way, we have to discount his exceptional recordings. I'd agree that, overall, Hamelin is probably the best interpreter, with a solid mix of technique and musicianship (particularly in the Grande Sonate and the Trois Grandes Etudes Op. 76), but for certain pieces I like certain performers. I think it's just a bit different than asking, say, "who is the best Chopin interpreter" or "who is the best Liszt interpreter", just because, when you dissect it to "who is the best interpreter of the full set of the Op. 39 Etudes", there just hasn't been enough attention given to them; there isn't much choice in the matter, really, so it's a bit limiting of a question.
Also, Bolet and Berman respectively,
obviously 