According to whitehatsec [0], Qihoo was caught cheating in a quality assessing certificatoin. The fact that there is a linux version for their product seems fishy to me in gereral. As an actual reason for deletion however I could come up with [1]. A whole compendium of really bad marks for security software.
cheers! mar77i
[0] https://blog.whitehatsec.com/hackerkast-34-soho-routers-hacked-3d-printed-am... [1] http://www.theregister.co.uk/2013/02/01/qihoo_government_warning_fraud/