Support from a not quite free service

I realized a ways back that I needed a third party to provide secondary DNS services for my domain and researched many optins and eventually settled on EveryDNS.com. I liked the robustness of the service and the price, free! Of course, they asked for donations and I was happy to provide one for their valuable service.

EveryDNS(ED) has since been acquired by DynDNS(DD) and my needs have changed and I switched to using ED/DD as my primary DNS host. This has worked flawlessly except for one domain. It appears that I ran into a bug with their system and they are not providing accurate DNS results. This is a problem and brings the question.

ED/DD provide technical support, but the response email states that it could take 4-6 days to respond. I can understand slow response on a free service, but I did pay for the service. To make matters worse, the issue at hand is clearly a bug in their system. At this point, I am frustrated waiting for them to respond and my website is having difficulties. Given that I paid, I think that I deserve a better response. Am I being unreasonable with this request?

One final note, my name registrar provides DNS services and so I moved the domain to them temporarily while ED/ED resolves the issue. This solves my problem, but does not resolve my my annoyance.

5/10/10 Update: The DynDNS Twitter team responded to my tweet on this topic.  They were helpful and highly responsive and resolved the problem on the same day!  Kudos to the DynDNS Twitter crew.