We aren't buffet people but we tried it once. It was just okay for us. Some of the items others rave about (zebra domes, etc.) just didn't knock our socks off.
Also, a PP had a similar experience to ours, you do all the work getting your own food, the servers were almost non-existent with refills and then you are suppose to tip them.
However, we really loved Jiko's and ate there more than once on the same trip.