I own one of these Pound cables for the original Xbox, and it works well for what it does. Does it make an original Xbox work on a HDTV? Yes. Does it upscale the original image? Only on the games that it is supposed to. If you are buying it because you think it will make Xbox games look as good as Xbox 360 or Xbox One games, it won't do that, but they will be playable. It's like watching a show that was shot in standard definition on a HDTV today. That's the best analogy I can come up with.
That said, it was a solid investment for me. But I own hundreds of original Xbox games that I bought years ago, and I still enjoy playing them. I even removed the clock capacitor from my original Xbox a few months back which I recommend that anyone with one of the earlier versions of the system should do since a leaking clock capacitor could possibly kill your system. But, I would only pay the lower price for the cable and wait for it to come back in stock.