I did not feel the new RP23 to be that much better then the 08 model I had on my previous bike. The boostvalve mainly affects the end of the stroke so you don't bottom out.
Of course this will largely depend on the frame, and how well the fork is tuned for it (and for your weight and riding style). I have heard others say the 2010 model was far better, but as far as I'm aware Push actually removes the boost valve if they get their hands on a 2010 fox. I would guess the real reason people prefer the 2010 model to the older ones is that it happens to have a better tune for their application (HV vs. LV / correct compression / rebound tune etc).
I got one on my Intense Tracer a week ago but already ordered a pushed van r from tftuned…