Has anyone tried one of these:

Musou 3RCA Composite CVBS AV to HDMI Video Audio Converter Adapter Mini Box Support 1080P for TV/PC/PS3/Blue-Ray DVD,black ?

The above "box" converts composite video and audio to an HDMI output. The HDMI is then sent to your HDTV. I am considering one of these "boxes" for converting LD, CED and VCR composite A/V to HDMI to go into my HDTV. I was wondering how the PQ would be.

Never used one of those, but I have heard that those boxes will "stretch" everything into a 16:9 image.

Otherwise not sure how it would look, I have tried a few different scalers but never got satisfying results , nothing seems to work better then just going straight into my hdtv from composite.
(Not sure if thats an option for you)

I'd put my money on something like this doing a worse job than what's already built into the TV.

Piece of crap....don't bother...I bought one of these cheap converters last year...tried it once, threw it in a drawer never to be seen again. You're better off leaving the picture size as is, or playing with the zoom.

Thank you for your comments. Let me expand with some backstory:

I have a Sony STR-DA2ES AVR with 5 composite video/audio inputs as my active switcher. With the exception of video 3, I am using the remaining 4 composite video/audio inputs. This way, I can switch inputs on the AVR using the remote. The AVR's composite video output then goes to my Bravia HDTV. Video 1 on the AVR is used to switch composite video from an HD-DVD player, Sony MDP-600 LD player and numerous CED players (4). Video 2 accepts the output of an SDP-E800. The E800 has an CDP-D406 and an MDP-600 LD players for its signal sources. Video 3 is unused most of the time. The 4'th video is used for my DVD changer and the 5'th video is for my DirecTV receiver. As you can see, I have a fair number of composite video sources.

Now, I am considering the purchase of this AVR:
https://www.amazon.com/gp/product/B06XKRWWSG/ref=ox_sc_sfl_title_2?ie=UTF8&psc=1&smid=ATVPDKIKX0DER.

The DN1080 AVR has one composite video input for SAT/CATV and I plan on using its video 1 composite input for my SDP-E800 (maybe). This leaves my DVD changer and my CED players out in the cold. I thought that 2 composite/HDMI converters would allow me to use 2 of the HDMI inputs on the DN1080 AVR to convert composite video from my DVD changer and my CED players. My HD-DVD and my Sony Ultra-HD players can feed their HDMI signals directly into the DN1080.

From what the posts indicate, a composite/HDMI converter is not the way to go.

Are there any other types of converters that might work? If not, I may have to use the video 1 input on the DN1080 for all composite video sources which would make my life a bit more complicated. (I would need to use an A/V switcher to connect all the composite videos into the video 1 input on the DN1080). I have an A/V switcher that Sony made some years ago that I could use. It has 4 inputs to 1 output and turns on when a video signal is detected on any of its inputs. About 10 minutes after the video disappears the unit shuts off. Since the DN1080 has a composite monitor output, I can use the output to send only composite video to the HDTV.