Hi Drew and Paul,I want to jump in here hoping I can be helpful. My company is the US based Visio developer for several dozen manufacturers of network equipment including Cisco, Alcatel-Lucent, Juniper Networks, and many others. You can see the list at http://www.shapesource.com/manufacturer/all
In addition to creating them, we post the files for free download at our web site with permission from the manufacturers. This offloads the distribution to customers and internal users. I've tried to download several from the "at last visio stencils" page and the links don't actually download many of the files.
In addition, I'm sure you want the quality of your Visio stencils to reflect the quality of your products. Visio images are marketing tools as well as technical and we treat them as such. I can explain the various behaviors, features, and image qualities that we program into our Visio shapes to benefit our clients and their customers but I won't go into it here. I hope you will forward this on to someone at Extreme who is responsible for providing the Visio content for your products. I can be contacted through the ShapeSource site if there is interest.