It's very difficult to compete with Marc-Andre Hamelin in the music of Alkan, but Jack Gibbons is every bit his illustrious colleague's equal. As far as complete sets of the Etudes op. 39 go, this is the best. In individual pieces, it's fascinating to compare Gibbons to Hamelin. Both have mastered the stupendous technical difficulty of the pieces, but where Hamelin is often cool and unruffled, Gibbons is mercurial and impulsive. The differences in approach benefit different pieces. In the Concerto for solo piano, I prefer Hamelin's tighter control of the sprawling structure to Gibbons's more impressionable response to each individual episode.
In the more compact Symphony for solo piano, on the other hand, it seems to me that Gibbons is the one who gets to the heart of the piece, despite Hamelin's effortless virtuosity. If you don't know Alkan's piano music, this set is the ideal introduction given its quality and value for money. From then on, you can supplement with Hamelin's Les Quatre Ages CD and Steven Osborne's Esquisses (and Hamelin's stupendous Concerto for solo piano for a more cogent alternate version), and you're all set for one of the most individual and fascinating voices of the Romantic piano repertoire.