During my testing, I found that the listener is capable of keeping up at least for a time on my machine. However, at some point, it fails to keep up, at which point it doesn’t return from Spin Some, which makes sense. However, if I close the talkers at this point, I would expect that spin_some would eventually return, which it never does.
Because I don’t like dealing with high rate items (hard to see), I slowed everything down to 10 Hz (talker/listener) and started 1 talker, then 1 listener, waiting for a bit to make sure things were operating as expected, then started another 2 talkers. It ran fine for awhile, but eventually (within 1 minute) the spin some stopped working. At this point, I stopped all the talkers, expecting the spin some to return. Never did. I was able to re-start a talker and the callback was still functional, but spin some would never return.