No issues here. I've mainly been using the composite signal and not tested RGB (I have the equipment on-hand/ready) as I just want to play some games!!! With that said, this works nicely and I realize without testing the RGB on 1 of my modified consoles is probably useless but posting anyway for others:
Monitors:
Sony KV-1311CR
Cables:
Genesis2 AV Cable
Systems:
Core Grafx (modified w/RGB, Jailbar fix)
Core Grafx II (unmodified original)
Original PSUs
Monitors:
Sony KV-1311CR
Cables:
Genesis2 AV Cable
Systems:
Core Grafx (modified w/RGB, Jailbar fix)
Core Grafx II (unmodified original)
Original PSUs