RE: Servos twitch on PCM!?
Some twitching is normal in 6 volt system when it's fully charged (a good reason not to use them) The twitch you're talking about at full deflecting does sound like a voltage drop problem. Check and recheck all your wireing and make sure you're using high enough gage. When in doubt use 3 gages higher than you 'should' if you can aford the extra weight, which isn't significant.