When I first installed the PCV/AT the rear O2 sensor bounced around from an AFR of 12 to 25 when at idle. I checked the exhaust system for leaks found none and resealed everything anyway, swapped the front O2 sensor with the rear, checked all connections on the PCV and AT modules and bugged the bejesus out of the guys at FuelMoto. I finally tried partially restricting the right exhaust and the sensor stabilized and acted more like the front cylinder. Using that as an excuse to buy them, I purchased Jackpot asymmetrical baffles and swapped out the 2" Rush baffles. Problem Solved! Could it be that 2" baffles aren't restrictive enough and causing some exhaust reversion? *shrug*
Both realtime AFR readings are now stable at idle and that aggravating decel popping is gone. After changing the baffles the AT modules did lots of tweaking, leaning up several cells. I haven't checked the fuel economy to see what I'm getting but I'm pretty sure its not as good as it was in stock trim.