the stihl 4 mix that is replacing the 25 cc two stroke is a completely different engine than the 4 mix blower engine. I have seen both engines do VERY well although I have seen a rash of the smaller 4 mix on trimmers with coils that would stop firing after getting hot. I don't think the blower recall is related to the coils as it is a different coil and I haven't seen any go bad yet.