Who has the most upside  ?  To me it's bender . He won't have the strength or low post scoring ability as Okafor , but I see him as a much better defender , more skilled offensive player, better handle and passing/ play making ability, ability to stetch the floor and get his shot off against just about anyone . 
I don't see Okafor as a good defensive player , he just doesn't have the agility to cover in the pick and roll , or ability to switch off onto guards/ wings . 
At this point , I would rather keep the pick than trading it for Okafor .