Since I sell both...
Actual-use reports back to me are the RS19 and RS29 are fairly similar, with the RS29 having more initial bite - ie it has been reported back that they are 'grabby' and not in favor vs. the RS19.
I probably sell the RS19 in a ratio of about 30:1 over the RS29 -- and the guys who have bought the RS29 usually don't re-purchase the 29s, instead choosing the RS19s. YMMV.
PFC pads are generally thought to be excellent pads, with Pagids frankly residing on the top of the heap. For pure track use, the yellows last a long time and take a real beating - AND tend to be quite kind to rotors. And usually howl like a banshee on the street. The (RS14) blacks are great track pads, but tend to munch on rotors at a higher rate than one may like...
Cooling is of primo importance with any high friction pad, the yellows really require superior cooling. I'd highly recommend a fan setup.
Something to consider is the possibility that the thermal capacity of the discs may have been exceeded -
3.4L, SC heads, 964 cams, B&B headers, K27 HF ZC turbo, Ruf IC. WUR & RPM switch, IA fuel head, Zork, G50/50 5 speed. 438 RWHP / 413 RWTQ -
"930 is the wild slut you sleep with who tries to kill you every time you "get it on" - Quote by Gabe
Movie: 930 on the dyno