for our cars i havent seen many options that were really worth looking into the mugen is made for our f-series engine not sure what u say so i cant comment but the DC one is the best u can get the overall gains are really small over all but at different points in the power band it raises above the 2-4 peak gain. so teh DC are carb. exempt so if ur in a mod crazy state u wont have any worries about taking it out for inspections or a cop giving u a fix it ticket... personally get the stainless steel (SS) ova the ceramic coating (CC)