Not sure, some years ago IC Markets had some mispricing with delayed quotes on USDRUB I noticed randomly. I just watched and compared it to free yahoo quotes and my datafeed. They delay was about 15 to 30 seconds but there was massive actions on interbank with high volatility. I did not arb that opportunity but when I asked the support they clearly said in written text that I can trade this and it is IC Markets fault if there are any delays in their quoting system. It maybe not that much delay as with GAIN but the cases are similar and IC Markets told me that it is possible to arb and profit from it as trader. It is certainly not the traders problem they said.
