I have used Ross, Arias, CP, SRP & JE. I usually use JE in all my personal projects, but I like the results that I am seeing with Diamond pistons.
Can't say I had any problems with any of the manufactures, but about 10 years ago I was noticing the same result with the Ross pistons that OneBad was noticing with the JE's.
For the last 5 years I have cool coated every set of JE pistons I have ordered. They are all still running in the motors they were built for.
Good luck with your JE's and have fun racing....