I recently bought an used MD1 to replace the board on my old one (which only displays a black image).
I tested the used MD1 with the RF cable and I got a little distortion on the image from now and then, specially on games like Sonic I and II. Yesterday I got 2 RGB cables, one for the MD and another for my Nomad.
The picture quality on the Nomad is great, but the MD still has the same distortion and it shifts the screen a few pixels between left and right. I'll try to post a video later on.
Is this a known problem on the MD / Genesis?