I been have PPA for the past 3 years. I see very few bladders. Most runners have hand held water. Most PPA runners carry 12 oz. bottles. This is only my opinion
In response to:
I read in a thread on this topic below that some claim it's difficult to suck water out of a bladder, especially at higher elevations when you're barely able to suck enough oxygen. Whereas with a bottle, you just squeeze the water into your mouth and your good to go. I decided to carrying a bottle for that reason.