Ask HN: Break my site?

Hi, For the past few months I have been writing a control panel and api for a Mumble voice service. Now before I launch the service I need some help beta testing but I don't really know where to get testers so I thought I would ask here.

My site is haithar.net and you can use the promo code hackernews to get a free mumble server to test.

Other than bug testing any other feedback on the service and how I can improve it would be appreciated.