If bitcoinbuilder went to 0.9, how many people would be able to sell at this price? Bitcoinbuilder is now a fake market because noone can possibly sell at their price EXCEPT those who have already transfered their goxBTC over to bitcoinbuilder before the close.

You can tell just by looking at the extremely low volumes. Plus, I believe the bitcoinbuilder admin is taking a 4% fee on each trade, and the 2% realBTC side he converts into goxBTC he claims, so effectively he is subsidizing it.