So, I’ve had my Denon X3600 for over 2 years, and loved it a lot. Works great, sounds great. My 5 ground level speakers powered by the Emotiva BasX A5. All good.
But - as usual - it’s time to change! So I’ve been eyeing the Denon X3800 for a while. Then I thought, why no love for the RZ50? 
The one thing that the Onkyo was poor in was very obvious - the Denon has 4 independent sub outs vs Onkyo’s 2 sub out (identical). My listening room is small and probably have space for at most 2 subs. So, I was not too concerned with that lack of multiple sub outputs.
The pros for the TX-RZ50 had more power and Dirac Live!!
So, I went to Lazada and bought the Onkyo (plus a free pair of Wharfedale D300 3D Atmos speakers).
Delivery was quick - think 2 days. So, today - since have time, started to do Dirac calibration for the 1st time (I’ve watched some Youtube videos earlier). When I learnt that it would require 13 points of measurements - I thought it would take a very long time. But in fact, I think it was much faster than measuring 5 points with Audyssey.
I ran the Dirac Live app from my Windows PC. It is so easy and nice to use compared to Audyssey.
I downloaded a Harman Kardon target curve for Dirac (to use as sample) and modded it to suit my place and speakers. I’m using:
External amp: Emotiva BasX A5 powering fronts (LCR) and rear surrounds
Front: Polk Reserve R200 bookshelves
Center: Polk R300
Front Atmos: Wharfedale D300 3D (up-firing)
Rear Atmos and surround: Polk TL2 satellites
Subwoofer: Kreisel DXD808
Bass shakers: ADX Bass Shakers
Played many of my usual Atmos/DTS-X demo clips and I am once again hearing things I’ve not heard before with my old setup. How could that be possible?! 
Atmos playback is superb and sounds so much better. Bass control is excellent.
Before calibration, I hooked up the RZ50 without the external amp. I believe I don’t really need my Emotiva anymore (it’s for sale now!).
Do I have any regrets getting the RZ50? Hell no! It’s excellent. Dirac Live is really a game changer.
I know the Denon will get Dirac Live soon - but it’ll possibly cost US$259 for the license or US$349 for the full version. US$500 for multi-sub support! Plus Denon’s Audyssey mic might not be usable for Dirac calibration (maybe, maybe not). That’s quite a lot of extra cost.