Todays modern pistons should all have correct PTW if your finished bore is on the money. We usually add .001 thou to about every build but it is not needed. The old days of--"I fitted each piston to the hole" is long gone as the materials used today have exactly controlled expansion rates.
The trend is to run as tight as possible to help reduce rocking and improve ring seal--I think that is playing with fire and no big deal for the average street or race engine--we go on the big side --I have seen a hundred times -- trouble from too tight---I have Never seen a deal where you could say--I won the race because I had mine to minimum. What looks good on paper is not what works in the world --
Have your bores dead on size or a tad over and you will never have issues with SRP--they are great pistons. The real answer to your question is determined by each piston brand and is set according to what material they use and its expansion rate
