So, sow, sew, after roughly 5 sessions on the Masame pivot cups, back to report.
I'm using the 98A "hard" pivot cups in my 139 Indy Hollow Forged with 88A red bushings. The pivot cups fit flush with the baseplate.
Initially they felt a bit rough/hard, but after a few minutes into my first session, they got seated and felt good. I chalked that up to the "honeymoon/confirmation bias" of new gear.
I waited until I got a few more hours on them before I checked back in here.
For the past couple of years I've been riding Ace Classics but had this set of forged hollows on ice. For shits and giggles (or to tempt a flare-up of gear madness) I decided to set them up. Obviously, the turn was way different, and it felt like my board was fighting against me/wouldn't return to center and I was getting a lot more feedback from the road. I didn't want to use shock pads, but was worried I might have to.
Based upon advice of my homie at the local shop and Pal GISM (sorry, can't seem to @ people here), I gave the Masames a try.
With the softer duro (Actual Indy pivot cup duro seems to be an enigma here on the forums, but the overall consensus is that they are off the A-Duro chart, maybe a thermoplastic rather than urethane), the Masames have eliminated my need for shock pads (softer ride), have also made the turn of the trucks feel like I'm more in control, and the trucks turn much more smoothly. They also seem to return to center better.
So, TL;DR, they're worth a shot if you're in Japan/have access to them. They come in four duros: 98A (hard), 95A (medium), 90A (soft), and 80A (extra soft). Color coded: all are blue; darker shade = harder. They cost 880, tax included.
There's more info (in Japanese) here:
https://masameskate.stores.jpIf you have to get them shipped overseas, honestly probably not worth it, but letter shipping from Japan can be reasonable.
As far as I know, they've only been tested/designed for Indy's and Thunders (seemingly the bulk of trucks ridden in Japan). I don't know the measurements/height/depth.
Let me know if you have any questions!