Just use RX. I think it's the best automotive product period fwiw. People can't believe my 89 Mazda 626 Turbo (GT in U.S) runs so well at 250,000kms. Apart from NGK Iridium IX plugs (done 90,000kms) and a rebuilt turbo engine is untouched. 400kms into another RX clean engine is silent at 2,000 RPM. Wasn't like that a week or so back I can tell you. Give solvent flushes a wide berth IMO. Cheers..s