They seem to be all over the place. Since there isn't a real OG strain that I've seen, there are varieties that to me look better than others. I was just at Aquashella a few weeks ago and I saw them ranging from $35pp to over $100pp.
I got mine off ebay from a seller and I won the bid on three huge frags. I scored like crazy. Some reason his auction didint do well and he let me stay on back to back weeks and he had all high end zoas. There are alot of sellers on ebay with then now pretty cheap bu they were high end or so I thought. A seller on here who was asking crazy prices for all his high end zoas and had these for 10 a polyp!