The real surprise is that Buy.com's response has been similar. Buy.com's email auto-responses of May 9, May 22 and Jun 18 all say "We will reply to your email within 24 hours of receiving it." Unfortunately, that's a lie. Again, no human replies. And no rebate. The original offer linked from Buy.com's web site said: "Rebate checks will be mailed in 8-10 weeks after postmark date of program." As the months go by, it looks like this one is a dead loss. For more examples of this rip-off, just put "KWorld" and "fraud", or any similar search, into your preferred search engine.
The moral of the story is quite simple: KWorld and Buy.com are liars. Don't buy anything from either of them, especially if it involves a rebate that they will, illegally, fail to provide.