The existing answer is incorrect. Yes, it does benefit.
Base power x stat boost is incorrect. Base power is not changed by stat changes, the actual Atk/SAtk of the attacking Pokemon and the Def/SDef of the defending Pokemon is. So if a Pokemon had 200 Attack and received one normal boost to the stat, it would become 300 (one stage gives 1.5x boosts to the stat). The base power of its moves would be unchanged.
Gyro Ball's base power is determined by the Speed stat of the attacking and defending Pokemon. Once this has been done, Gyro Ball functions the same way as any rather move, with all the stat changes factored in. Say Gyro Ball's power ended up as 80; after this, it's effectively Iron Head without the flinch chance.