When we buy BTC using USD on MtGox,
Does MtGox charge 0.6% of the USD then do a trade, or does MtGox do a trade first, then charge 0.6% of the BTC we receive?
Similarly, when we sell BTC for USD on MtGox,
Does MtGox charge 0.6% of the BTC then do a trade, or does MtGox do a trade first, then charge 0.6% of the USD we receive?