I have the Pioneer VSX-LX505. It is basically the same as the RZ-50. The RZ-50 has the THX stuff, and the LX505 has a couple of features that the RZ doesn't. I have had the unit for almost 2 months now. So far, I think the Dirac has made a huge difference in my system. My surround field is better than it has ever been. Dialect is clearer to me, I can listen at lower levels and still hear what people are saying. I am hearing things in movies, that I never heard before. I had a Marantz SR6013 that stopped working before this. It is in for repairs. Always had HDMI issues with the Marantz. Most of the time when I turned on Apple TV I would get an 8" white flashing bar on the bottom of my tv. Never even used CEC with the Marantz. I have CEC turned on now, and no issues with the Apple TV connecting. CEC seems to work great most of the time. Sometimes though, it will also turn on my Pioneer UDP 4k Blu-ray player. Only happens every once in a while. The web interface is really helpful. You can even see the temp the unit is running at. It also shows if the fan is running, and I have never seen the fan come on at all. I do not have a tv capable of doing the HDMI 2.1 stuff yet. Most of the people that I have seen online that do, say that it does work well. I also do not use the amps in the unit. I have an XPA-5 that runs my main speakers. I have not had any issues using the preouts to it. This unit has been one of the best upgrades that I have done to my system in a long time. Hope this helps to put some of the questions to rest.