I've got one spring with UHMW on the car, the other is ready to go on but I haven't gotten that far yet. I would say it's definitely worth the effort if you already have the springs disassembled for cleaning, since it's pretty trivial at that point.
Too soon to say for sure, obviously, but I am very encouraged by the results so far. There seems to be a lot less vibration coming through the rear suspension than before. However, it does seem that I am bottoming out the rear suspension more easily, so I may need to do something to increase ride height a bit, or perhaps go to stiffer shocks/heavier shock oil.
Come to think of it, I believe I had 30 weight in the TR3A. Maybe I'll just move them over.
BTW, the $50 roll of UHMW from
MMC is enough to do two cars. I want to keep my other half, but you might be able to find someone willing to split a roll.
PS, based on advice from TeriAnn Wakeman, I used the .0065" thickness of UHMW.