Even though it's a bad topic, I'm going to play along
Actually I'd like to hear Beethoven play the Liszt Sonata (think about it...)
But out of that group, I'll take Busoni
Reason - by many accounts, he was the most awe-inspiring pianist of the first half of the century - Rubinstein (Artur) said that he was the greatest pianist that he ever heard (until Sgouros - I'm SO sure!), as did Schnabel, and others...in fact, he was the only pianist whom Horowitz had considered studying with at the time that Busoni was still alive. He inspired fear into the hearts of his collegues. I believe it was Gabrilowitz who thought that he saw Busoni sitting in the rear of the hall during one of Gabrilowitz's recitals - Gabrilowitz said that he was so psyched out that he played like crap (only to find out later that it in fact wasn't Feruccio!). His equipment must have been colossal, as well as his vision, variety of touch, and the sheer will of his playing, the intensity...
I imagine that he would have held it together architecturally, like a great cathedral, without losing any of the romantic rhetoric. It would have been a gigantic reading, maybe the best ever...think about his 13th rhapsody...
Poll
Liszt Sonata performed by...?