I'd have to disagree with cmg. I personally think that El Corpus Christi en Sevilla is actually one of the few very straight-forward pieces of this set. There are some tricky passages in the right hand, but they are pretty static. I would say Lavapies is the one that I hear utterly ruined the most-often; probably the most musically challenging due to very difficult voicing. I would say technically Triana lives up to its reputation, mostly due to its unrelenting nature and the hand-locking. Rarely is it performed at tempo.
And if it isn't utter sacrilege to say so (and I daresay it is, but I'll risk wrath by doing it anyway), I rather think that the Godowsky version of Triana is superior to the original (and somewhat easier to bring off successfully, its considerably more notes per square centimetre notwithstanding) - and I say this as one who admires Iberia immensely...Best,Alistair