I can see the benefit of this application, however there are a few things that can use some improvement. For example, a little documentation would be nice, typo in the "Average Query Time", and a "Overall DNS Server Performance" key and why and what does it mean would be nice. Also if I let this application run to complete all 10,000 querys it crashes. A nice side component would be an auto generate random list of 1000 domains from your website to d/l, so you can test with new data and any time. Performance can be based on your internet connection speed and the DNS resolving speed, physical location from you to the server... etc. Some queries will take longer, and that is to be expected.
Needs some polish, but good app