Sorabji's music is very unique. I, personally, don't really like the Opus Clavicembalisticum. However, I do like his Gulistan, his Fantaisie Espagnole, and some of his etudes. Those, IMO, are really good music.
I disagree that Alkan has composed the most difficult music of taste and beauty. There are many twentieth century works that are both beautiful (to me) and far more difficult than any Alkan.
I guess, after DarkWind posting the OC, I really don't need to send you a Sorabji score to see what it looks like. The Sonata looks like more of the same kind of stuff.