PS: I have very large hands if that's useful. 
I have absolutely no idea and no interest in what others have posted here, but this PS is particularly amusing. No, "very large hands" are not an asset. According to the late virtuoso, Earl Wild, large hands are a hinderance. Smaller hands, that can comfortably handle an octave, are superior. Their very size forces a comfortable and natural hand position, that minimizes habits that lead to tension. I'm sure this insight from a great pianist (Wild, of course, and not me, certainly) will only stir up debate and derision from the rest of you, but there it is -- a valuable insight, nonetheless.
As to your grandiosity about learning the Rach3, with limited experience, go for it. I doubt, very seriously, that you are some undiscovered pianistic treasure that critics have been praying for, but, if you, by some remote statistical chance are, then dazzle us. Frankly, however, this type of delusional thinking is enormously depressing, if one takes it seriously. Honestly, I cannot. If this isn't spam, it should be.
Very few can play this piece of such enormous technical and musical difficulty with any assurance and artistic originality.