I think PF pads are notorious for generating a lot of brake dust. I very much doubt changing discs to PF would change the amount of dust generated. To be honest I think PF pads are overkill for road use anyway. As you say, they cause lots of brake dust and really wear out your discs much quicker than other pads, although the benefit is they offer great stopping power. Ferrodo DS2500 offer a good compromise of low brake dust/disc wear and offer very good stopping power for fast road/occasional track use. PF discs with the Ferrodo pads are apparently a really great combination, but as you say, the discs aint the cheapest! But hey, you gotta pay to play as they say