The z man ones will be out this month and have a great keeper on them. I've looked at a few knock offs and they have all been really cheaply made. That's a damgerous thing when you're using such a small, lightwire hook.
The heads on eBay have a Mustad 2x Ultra Point Black Nickel Steelhead hook. Much stronger than the hook on the Zman heads. The Zman heads in my opinion don't have much of a hook, I have used them both.