The "issue" or downside is the limited availability for award seats in premium cabins, especially ex-Australia. If paying for a regular commercial ticket, you can travel almost any day you like, via whatever routing you like, and with companions on the same flights. but when using award tickets, you can be very limited around dates, routing and it can be almost impossible to find multiple premium cabin award seats available on the same flights much of the time. If you can find the availability, then its great value. If not, then its of no value at all.