Is it rated API-SM? Use it.
Try it and let us know how she runs. If the engine doesn't like it, it will let you know with increased racket and lowered fuel economy. Your straight Ilsac GF5 lube is way under-additised to give the cats 9 lives and the engine 1/2 a one.
Note that 100PPM additive is just 1/2 gram out of 5,000 a likely EPAW treat rate for a typical sump.