Yes I am running stock pistons. I have a second set to drill out to 1.3mm but I never have.
I typically run 500 cst black bladder and blue o-ring.
With Sorex tires I typically run Green rear springs and Black/Blue fronts (carpet mainly but I'm trying it on asphalt this weekend) I have found this makes the car stand up really well with my carpet setup to stand the car up and go straight when you mash the throttle in mod. I am hoping to achieve the same setup on asphalt. For my driving it was the only way to get match the big boys. Will update more on Sunday.