Hi Dave,
Can't remember exactly the problem but I decided against KZLG for a reason and went with the FPO's. I think I had a look at the prospectus for the notes and there was a condition where the company could buy them back at any time (or similar) for a paltry premium. If they enforced this and the stock had gone thru the roof you'd be looking silly. I'll see if I can find it.
Cheers,
Ed.