It will be cheaper if you pay fees through Bitshares, BTS, not bitcoin or any kind of other altcoins. Nevertheless, withdrawn 1800 satoshis is always not the right decisions. I just recommend to switch bitcoin (whatever amount you have) to other coins, like Bitshares, Dogecoin, Ripple, then withdraw via those gates, with fees paid in Bitshares, then you will save a lots in fees.