Should be noted that this is generally considered the "bad" one. Worse than requiring a separate audio output, the colors are generally way off when you get them, requiring you to mess with potentiometers inside the unit to get it right - pots that strip very,
very easily. While my unit is no longer as cyan as it used to be, I swear that the green/fuchsia balance is very subtly off, but can't tell which pot changes that, or if I've already stripped the pot in question.
The "good" one apparently looked like
this; the one you linked to (and which I own) is a Chinese knockoff thereof. My understanding is you don't have to screw with pots to get a good image out of this one, but never having had one, I couldn't say. Still requires a separate audio thing, though. (YMMV on how big a deal-breaker this whole pot thing is, hence the quotation marks around "bad" and "good" here.)
As for the eBay one linked, a guy from SA got after I mentioned in their retrogaming thread that somebody in here was suggesting it, and he said it just
worked, no potentiometer hassle necessary. On the other hand, whereas even the Chinese knock-off was made of metal, the eBay one was clearly 3D printed - and arrived at the guy's place with the poles for the screws holding the top on snapped off. Seller was all too willing to replace the thing, but the guy on SA just asked for a refund instead and went another route.