Hey man, I've run the regular PPs (190/50) at Sepang over 5 trackdays. I'm now running medium PRs. The difference is that the PPs do not require a warm up lap, whereas the PRs did, before you can get down to crazy lean angles. I have not tried the PP2CTs, but if anything, they are supposed to be an improvement over the original PPs. And those PPs can take a huge amount of hard riding before they show any appreciable wear.
The downside is that the PP front has a profile that makes it a little heavy to steer, compared to the race-like PRs. Also, in average ambient temps that we see in this part of the world, after the 5th lap or so, the PPs will exhibit a tiny amount of squirm at the rear on corner exits. Nothing wild, but enough to tell you to take it a little easy. The PP2CTs would probably have that problem cured. I will be changing to them as soon as Joe's batch of 190/55 2CTs come in next month.
I believe that the PP 2CTs are a better choice for street riders who like to take in the odd trackday. PRs better suit those with race intentions.
Just my .02.
Cheers.