The other thing I have been using the past couple of years is a two piece piston. I tried plugging the wristpin and had plugs come out, and really unless you use a drag racing type of pin boss the completely plugs the pin bore you are always going to have a passage from one port to the next. I initially designed this to get rid of the wristpin hole, but because I could make this round instead of cam shaped, it has worked out mechanically better. I don't really have rattly pistons they seem to seal really well. I can run them pretty tight even though the ones I have been using are not a high silicon alloy. I think using 4032 grade alloy would make them even better.
The pin boss connects to the connecting rod like normal, and the the boss threads into the piston itself. It keeps from unscrewing by the threaded bolts. and the bolts have c-clips to keep them in place.
the one on the left was run for quite a while so you can see how uniform the wear is all around. Or maybe not the picture is a cell phone pic.
The only issue I have had is the the boss to piston joint starts to get loose after 40 or 50 dyno pulls. Not very loose, but enough I swap them out. I think plenty of longevity for my application. I have been working on a ACME thread version, as I think deeper and more perpendicular surface area will extend the life. I haven't machined new ones yet as I like what I have, and like all of you, waiting for the Ryger thing that may make all of this outdated anyway.
You are welcome to make your own just give me credit.

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