I have the PF60 - which is supposedly better in every way. I don't see (or hear) a difference at all - but my power is pretty clean.
I bought it because it was really cheap (TigerDirect had a clearance lot for $149) and because it had 12 outlets in 6 separate filtered banks with one on the front. Oh yeah... and the LCD readout looks damn cool IMO.
Doesn't do anything that a $12 power strip can't - at least in my experience - with the exception of selectable switching and delays which is cool.
In any case - if your power is that 'dirty' or 'noisy' then it's always better to try to fix the problem at the source rather than mess with it at the end. I've never had big problems so I can't say if it would make a big difference with noise - but my guess would be "not much but slightly better".
Basically, the only reason I could even justify paying the price I did was because I would much rather organize my power cords and distribution in the cabinet, than have an even bigger rats nest behind the cabinet and have to use two 6-outlet power strips on the floor.