I have run PFC Z pads on the street and for autocross for the past 5 years or so. They wear well, are not very hard on rotors, and only ocassionally squeak. Pretty good pads overall. Absolutely do not do an open track DE event with these unless you are still on stock rubber and will not be running the car that hard. There is no such thing as a good pad for the street and an open track event because the heat range of operation in these instances is so different. Slap a set of PFC 01 pads on the car for DE events, it will only take a couple extra minutes when you are changing your tires.
auto cross won't tax the brakes any where near HPDEs.
So far the "easiest" pad I have been able to get away with on the HPDE circuit is the Hawk HP Plus. It will fade a bit, predictably so, it does last a good 400 plus track miles and does not eat into the rotor. Added benefit of being able to drive it to the track.