I used this a few months back when it was last on offer but found it to be very expensive in the long run.
It does clump well, is indeed flushable & good odour control but I didn't find that it lasted that long at all. That, and with the grains being fairly small they got stuck to my longhaired cat and trailed all round the house, onto furniture etc. Probably not such an issue if you have a shorthair.
I now use the Cats Best OkoPlus which is also flushable/clumping/organic.