Best 9 channels power amp?

New to separates and looking for advice and first hand experience from this community. What power amp would you recommend to power a 5.2.4 system? I would rather keep it to just 1 amp due to space constraints. I have been researching the yamaha mxa5200, monolith 9x, and emotiva xpa gen3. All have plus and minus points. 

Yamaha is well established as a brand and it has a bridge load function so that you can use 2 amp sections to power each of the fronts. It has 11 channels so this would allow it to power 9 speakers with that function on. While rated at 150 wpc, audioholics measured it to run at about 65 wpc with 7 channels driven. 

Monolith is rated at all channels driven with 3x 200 wpc and 6x 100 wpc. I dont know much about their reliability and sound. There's much less reviews on the internet about them than the other 2. 

Emotiva has a 9 channel which has 5x 300wpc and 4x 65wpc. I dont know how these measure as they state it is 2 channels driven rather than all channels driven. I also read the sound is muscular rather than refined. I also read some bugs with their amps. 

If anyone has any suggestions I would appreciate it. 
Too few appealing options for a 9 channel amp.  I'd go with a great 3channel amp for the L/C/R and a 6channel for the rest.
+1 kr4
The LCR channels are the most important . So a good 3 channels amp.( McIntosh MC 303 ) ( Krell Trio 300 XD)  ( Bryston 6B SST²  ) 
For the two surround and the four height speakers ; (AT526NC 6-channel Amplifier , class D.)
It depends on your budget, on your speakers, on your HT processor.

Here's what you do. Go find your monolith thing. Or any multi-channel amp. Really does not matter. Find the best one you can. Listen to it. Okay. Then go find any stereo integrated amp. Any. Really does not matter. But just for fun, make it one less than half the price of the monstrosity. One fourth. You think I'm kidding. No. Really. Does not matter. Just go and listen.

Then if you can stand the shock of just how awful multichannel is compared to even half the price stereo, buy whatever you want. At that point it won't matter. But at least you will have given yourself a sporting chance at a good sounding home theater system.
There is no "best" when it comes to a 9 channel amp. Just too many channels and power demand to do it right.

The Monolith is made by ATI Amplifiers in the US, and would be the best option for pure power. Emotiva does make a decent amp too. If I was the OP I’d use an upper end AVR as the pre, and have the following configuration: AVR running the atmos speakers, with an amp driving the 5 channels. Run the AVR’s room correction and you’re all set.

For a 5  or even 7 channel amp there are lots of options.  I’d go with either Outlaw Audio, Adcom or Emotiva. All are buy online. The Adcom only has the one model 5 channel, at 200 wpc and almost 100 pounds, so that might be overkill depending on the speakers being used.
Millercarbon. Previously I had a Cambridge audio cxa81 and now I am running the naim uniti atom for stereo sound in my living room. I completely agree with you the sound is much better than on a multichannel avr. However running my home theater I do prefer to have the 5.2.4 I mentioned. Gives me the dolby atmos effects etc. This is why I'm searching for a multichannel amp. 
213running thank you for your answer. It's exactly what I've been thinking. Doing all these hours of research and ultimately I don't think any one company really has an amazing multichannel amp ie more than 5 channels. Like the yamaha mxa5200 for example which touts 11 channels of 150 wpc. This is on par with the denon x8500 so it defeats the argument that separates offer more amp power. 

The only way to really make use of separates in a 6+ channel situation is like you said... 2 or more power amps. 

I have a different thread where I ask about running the Marantz SR8015 with an external 2 channel amp. The marantz has preamp mode too to disengage the 2 front channels. This would be similar to what you said and would allow for 2 external driven channels and then 7 channels running off the SR8015 (at stated 140 wpc). 

Thanks again I think your answer gives me some perspectives to think about. 
Thanks for suggestions everyone especially since I'm learning a 1 box multi amp doesn't seem possible for what I want. Millercarbon maybe I misinterpreted your comment and this is what you mean as well.