I do not have option so can't say from experience with Stars but I can make a guess and say yes as bank transfers normally do have fees and yes there is always a currency conversion fee to convert any currency it is normally a percentage somewhere between 1-3%.
I withdrew from Stars yesterday. They convert at the current exchange rate and do not charge a fee. I received the funds within a few hours. Quite impressed to be honest.
Last time i looked, which was last week, they said the minimum transfer they do is 5000 USD...
They claim it could take a few days to approve the transfer, then it is about 3 days or 4 depending on the bullshit.