I read about the new flush in the Amsoil magazine. Have not tried it yet, but will in the future. It's not solvent based. Their old engine only flush was solvent based. With that said I would be running RX just like you are doing.
AMSOIL Engine and Transmission Flush (FLSH) helps restore fuel economy, increase operating efficiency and reduce emissions in gasoline and diesel engines, and automatic transmissions. Its potent, detergent-based formula cleans sludge and deposit build-up, promoting lower operating temperatures and reduced oil consumption. AMSOIL Engine and Transmission Flush is safe on parts and can be easily disposed of with waste oil.