Composite and RF are bad video connections. That is why retro gamers are trying to find better video quality solutions. This is one of them. This basically converts the analogue RGB signal coming from the console into something that many non-European televisions can use. That signal is Y/Pb/Pr, more commonly known as component, and while it is not as great as RGB, it is still an amazing video quality standard.
Let me begin with a warning: Your HDTV might not like the signal from your retro console being connected via this device. This is not a fault of the device itself, HDTVs are just picky on what signals they like to receive. I would only recommend using this on a CRT or a Samsung HDTV. This device only converts the RGB signal into Y/Pb/Pr; it does not upscale.
Now that we have that out of the way, the image looks amazing. This is definitely the best way to play your old consoles on a CRT that does not accept RGB input. It is only $50 US (excluding shipping, which depends on your location), too, which makes for a sweet deal, and for the quality this device provides, I cannot complain. One minor note is that some do not use the correct colours, and that can be changed by adjusting the potentiometers.
Now, one glaring negative about this device is that it does not output audio, which is a real issue if you care about the audio at all, but the audio can be added with a relatively easy modification, or you can buy an adapter, but the one I have is really finicky, and most of the time, the image would have a pinkish tint. Another thing I should note is that you will need to buy real RGB SCART cables to use this. SCART is an all-purpose format and can carry composite, S-Video, Y/Pb/Pr, and RGB, as well as audio. Composite and S-Video through SCART will most likely not work with this device.
Overall, it is a nice converter, and it is a lot better than the generic SCART to HDMI boxes, which tend to have input lag, and many of those are dysfunctional, not working with many SCART cables, such as many of the cables made by retro_console_accessories, and I do not think RetroGamingCables.co.uk cables work very well, either. This is no Framemeister or OSSC, but for the price, if you game on a CRT, it is worth it. Also, be sure to use high-quality component cables, as many of the lower-quality ones introduce noise.
Notes: 1. I have not tested composite video as sync or luminance as sync. Composite sync (also called CSYNC, boosted sync, clean sync or raw sync) works very well with this device, though. 2. Super Nintendo consoles’ composite sync is off-spec and does not work with all HDTVs. Sony, Vizio and Panasonic TVs are known to cause issues with the Super Nintendo’s sync signal, and what happens when using incompatible TVs is that they will only show a black screen but will recognize a sync signal.