I have to manage something like 20 of them for work only because we have Protools, otherwise we would not have them. Waves does not require them anymore so no issue there. I've had at least two dongles fail, good old flashing LED mode means good bye dongle from my experience. Ever try dealing with PACE when one goes bad? Not a good experience. They sent me a replacement, it didn't work as it was registered to someone else, so I could not activate it or install my software. As a temporary solution I ended up using my own personal dongle until we could straighten this out, it took months. Oh yeah, after that they wanted to charge me $50 to transfer my license that I put on my own personal dongle to the new one, nice. I've other bad experiences with PACE dating back to the 90s when they did the keydisc limited number of installs on a floppy drive, with installs mysteriously go missing.
Oh, and the worst installation experience is a combo of anything Avid and iLOK and having to do it about 20 times. That alone makes me want to never use either of these things ever again.