I would stay away from the Retrobit AV cables if I were you. They are cheap junk. I bought a pair for my model 2 Genesis. The cable feels thick, but up where it splits to the red, white and yellow plugs, the wires are extremely thin. Gold plated connectors is mostly hype, and definitely wont make a difference if the cable is sub par from the start.
You can turn your RF adapter into dual mono composite cables, no soldering required. All you need is your RF adapter, composite AV cable, a wire stripper, a few minutes. See here:
viewtopic.php?f=25&t=15118&hilit Additionally, if you can do some light soldering, you can easily make your own cables. All you need is a 9-pin mini DIN plug (costs a few bucks) and some composite cables. Best part about this is you can pick your own cable, and you'll probably pick MUCH better quality cables than the Retrobit uses.