Capstans don't really spool to collect; just grip. The coils feeding on, but also off; so there is no power loss/speed gain like a winch, comealong etc.
i had oine and didn't have good luck with it, maybe expected too much; but i beleive RBTree has liked his, read other good 're-views' here.
Couldn't lift, then lower through the drum as friction device, the capstan itself is a specialized aluminum to dissipate heat faster, from the gripping of the rope.