@manfromafar Don't know about the backplane, but the controller, with up to date firmware, supports 8TB Drives - I have one of them in Pennywise at the moment.
@whateverUsayman : their website is stating these API's are only used to trade and the API cannot withdraw funds.
I have not used their services however, since the fact you have to pay for everything with bitcoin (no fiat options) is a showstopper for me.