Plugin to find a Site using a Plugin/Theme on Network

I have a big network (with over 2000) sites on it. When testing upgrades I'd like to be able to look for sites using a certain plugin to see if it is still working on their site or broke anything.

I have looked at the plugin and theme stat plugins here:

http://wordpress.org/extend/plugins/wpmu-plugin-stats/
http://wordpress.org/extend/plugins/wordpress-mu-theme-stats/

But both of these don't seem to be working on my network. I think it is too large and just times out to a blank screen after a while.

Does anyone know of any other plugins for looking up sites using plugins/themes. Or is there a way I could do it by looking at the database?

Thanks,

~Jeff