Okay so I updated the original post with all the latest info/pics of the new version modification. I even changed the title because as far as I can tell this is just for the this caliper. Anyway, you can read the OP but essentially it does work well, is it the awesome pedal I had with the RPV's at the MC? Sadly no, it is a much more subtle improvement. It essentially brings the pedal back to where it was with the stock calipers, the pump up is gone, and the pedal is firmer and more consistent. So it is good, but I am spoiled with the initial mod now so...
The pedal always stays well above the throttle pedal, it is better in every regard, it feels like more but by my measurements it raises up just 1/4 inch. It is also a fairly easy modification for even an intermediate DIY person, if you installed these calipers yourself and have a drill and a vise, you could do it.
I did try the 4 PSI RPV's but they did cause pad drag so those are a no go. I tested these RPV's on the bench, the 2 PSI valves are spot on, but the 4 PSI valves are more like 7 PSI so... Even so i took more careful piston retraction measurements of each piston this time and found at least one inside piston was retracting less than the outside pistons. No drag but most pistons were .004 -.005 and one was around .002. I pumped i tout and pushed it back in a few times and it seemed to improve so...
Do I need new seals already? Regardless the 2 PSI works with no drag, but you can't do much more than that it would seem.