We did not do the balloon ride because we had done one previously in Turkey, but friends of ours took it and said it was great. Several people did it and they all seemed to universally like it (but perhaps that's cognitive dissonance affecting their evaluation too). Whether it's worth the cost is a personal decision, but given the expense of the entire trip and that it's probably a once-in-a-lifetime experience, I'd say it's likely worth doing if you can afford it.