I have some PP8's and they are just fine for me. If you do a search on the forum you'll fine plenty of threads on JEBAO powerheads. I believe the PP series is the older series and now they have the SW series which is the newest version. Most any type of wavemaker is going to have some noise depending on what type of mode or wave you have setup. However, I don't find it that bad to me personally but some people do. I've even heard people complain on the super expensive vortechs and maxspect gyre's that they can be noisy also.
Reliable is up in the air. I have not had one fail but some have and most the threads are a mixed bag of replies on how reliable they can or can't be. You will have to take them offline and clean them every few months. I use the JEBAO powerheads and return pumps and they have been flawless for me for almost a year. However, I do clean mine every month and that maybe too much but It's easier to keep track and log for me.
