If you have and use the DA-200 collet system from any manufacture your heads probably get all chewed up from slipped wrenches, then the channel locks and then finally, it takes the vise grip to get that head off. It seems to be the nature of the beast. small tools taking the beating of everyday use. You just need access to service for your tooling. You need to be able to pick up the phone or drop an e-mail and have ya a new one. So next time you get bad head. You know what to do. Get a new head from Eric's Tool Room, Inc.
http://www.ericstoolroom.com/ home page
http://www.ericstoolroom.com/DA-200.html new collet system
http://www.ericstoolroom.com/badhead.html replacement head