The product claims to support speeds of up to 200Mbps. That may be true, but this isn't the speed you're likely to see. I my situation (a typical house) I get around 20Mbps. It's certainly a good connection, and connects quicker than a wireless connection, so it fixed many of my connection problems related to wireless.
In addition, I bought from "logsol" who shipped me some units that came from a BT Vision setup. They were unused, but they were not boxed as the retail product, and they didn't come with any instructions. I got instructions by looking on the BT Vision help pages, but I expected a set of ComTrend adapters in a ComTrend box with all the instructions etc.