Used several exchanges and didn't see this or close function even once... So... Probably there is none 
that sucks - how are you supposed to do comparisons to make decisions.
My preference is to mine coins in the tank and sit on them - then sell once they go up.
seems like everyone rushes to the coins that are selling high, but by the mine you mine anything worth while they've dropped again.
well - if 'hackers' could penetrate the system there - LOL....
they should have taken the software while they were at it
