Depends, what your co-worker wants to do with the phone.
I have a BlackBerry Bold and find the Nexus hard going for emails and texting compared to the BlackBerry - you, have scaleable fonts and that is missing from Android. If, you just want a business phone for communication the BlackBerry wins hands-down.
On, the other hand the Nexus 4 is far superior if you wish to browse the web, play games, etc.