I don't recall that many in Rocketland, but on the Gold Wing site (www.gl1800riders.com) a lot have used them and they, for the most part, are pretty happy with them.
I am using them right now as you can't get the big 240 rear balanced. I think there ok and have only tested them to 160mph they take a little to get settled in as the drop when you stop rolling. I am using them in the front and back. when I get a steering dampner mounted and the engine mods done I will be testing them at a higher speed. Pound for pound I wish I could get it done on a computer but if your not running as fast as I am I would say they are fine.
OF course you have a R3T and I don't know if you can balance them but I think they can and If I could I surley would instead of the beads. Its not that I don't trust the beads its that I really trust the computerized balancers.
Only downside I know of to using beads is that when you bleed air from the tire or when filling with air you'll have to keep the valve stem above the 4 and 8 o'clock position so the beads don't blow out or clog the valve!
I ran a 205 series Potenza on my VTX 1800, that was conventionally balanced, without any issues.
I ran with the liquid type that balances and seals if you get a puncture up to a 1/4 inch they say. Find-A-Flat II, is holding up rather well as in no flats in say 10 grand in the front and 20 grand in the rear. Knock on wood