I can tell you this is a quality product. You won't find much in the way of reviews because it is not a consumer product. It is built for installers.
I just checked the web site and it appears because the line has been discontinued the spec sheet is no longer there. This is why you can get these so cheap right now, about 1/3 msrp.
The big deal on these particular units are, first, they are not sacrificial,meaning they can take a shot and then reset. They also filter the incoming line to remove noise, plus have 12v switching capabilities, and are built like a tank.
They meet and actually exceed UL1449, clamp @ <300v. I have several in use throughout my home. If you are looking at belkin these are in another league and am sure you won't be disappointed.
Ethernet filtering??? Not sure I know of any product to "filter" ethernet. Why would you want to in the first place? It's all behind other electronics anyhow.