I don’t think the M17 does Atmos.
Of the two the OP selected, the MX160 has roomperfect, which is the best option for room correction.
But I would recommend waiting. Next gen pre/pros with hdmi 2.0b or even 2.1 are almost here, and 4k with dynamic HDR should be good enough for most people for the next 10 years, like 1080p has been.
The Classe sigma SSP mk2 does atmos, but you could also look at the Marantz 8802.
The Mcintosh MX122 is also an option. It’s the baby brother of the Mx160.
Keep an eye on the HDMI version of the units you buy. Without at least 2.0a, you can’t get HDR, which is probably more important than 4k at this point.
I have the avm60. It performs great, but the sound quality is relative depending on what you're used to. Don't get me wrong, the SQ is very good. But in the context of the rest of my system, which has fairly high resolution, it brings a slightly warm sound and I believe holds back the system on resolution when watching movies. If I were to do it over again, I would go with the Krell Foundation.
The Lexicon MC14/Bryston SP3 is a nice sounding unit, but it has a very laid back style of sound. I think it's a combination of the digital board and the slow slew-rate Class A circuits. It could also be that there are no localized power supply filter capacitors directly at the circuit. It is a massive power supply with a couple of 100uf post regulator caps and that's what powers both the digital board and the analog sections.
The Krell processors are more forward with a lot more attack in the sound. Definitely more exciting for home theater. However, the Krell doesn't support atmos at this time. One of the things I like about Krell is that they use linear power supplies for all circuits, including digital. Many processors will use linear for analog, but then use a switching power supply for digital. The Krell Foundation 4K is the only thing current right now.
The Marantz AV8802A (or even AV8805) is a very nice unit. It has a very good size main power supply (larger than the Bryston). It uses a rather slow op amp for the DAC I/V section, but Marantz has a lot of localized capacitors in the DAC board. It also has very good power supply filters on each of the individual discrete analog output boards. I would put the Marantz as a serious contender.
The McIntosh processors are liked by many. I believe it uses all op amps (no discrete circuits), but they also have very good power supply sections.
As far as Marantz vs McIntosh, it's difficult to say which would be better. Marantz can be sold for a cheaper price because they have a massive distribution and sales network, so they can re-coup investment easier. The McIntosh are not going to be sold nearly as much as the Marantz, so the cost is significantly higher. It's hard to say what would sound better. the McIntosh definitely wins on front panel and asthetics. though, I have heard that their processors are buggy and that McIntosh never fixes firmware.
In November, I picked up an Integra DHC-80.2 from Accessories4less. It's a factory-refreshed 2011 model. If this is what Onkyo/Integra was doing seven years ago, their current products must be really impressive.
Their current flagship is the DRC-R1, but they will soon be releasing the DRC-R1.1.
Both are 11.2-ch featuring Dolby Atmos and a wide range of other decoding schemes.
Although the 2011 model I have isn't the latest and greatest, it has a fundamentally excellent sound, excellent component isolation inside, and a far better selection of codecs, surround enhancements, and room correction software than my previous AVP, a 2013 $599 model from Emotiva. The 2018 R1.1 model will be all that much better with two more channels (11.2) the latest codecs (e.g., Dolby Atmos), and support for wireless -- Google Cast, AirPlay, Wi-Fi and Bluetooth, and streaming services including TIDAL, Pandora, Spotify and TuneIn.
That should keep you busy for awhile.
Current MSRP for the R1 is $2500, but expect the price to drop when the R1.1 is released.
@ Auxinput, thanks for your thoughtful input. It seems there are several manufacturers bringing to market new/updated processors for 2018. I was going to settle for the Foundation 4k despite it's shortcomings and I'm glad I waited because there are some good candidates that will be available in the coming months; If anyone has experience/insight I'd appreciate you sharing:
NAD M17 v2
EMOTIVA RMC 1
Indy Audio Labs ACT 4
I'm still using a wonderful sounding Arcam AVP 700. I upgraded the motherboard for $400 in 2008 & it's been perfect ever since. I need to upgrade to newer BD codecs/HDMI etc. I really cant afford what I used to because I own a home now but the Integra DHC & DTC models from 2008-2012 look real nice. I know they wont match the sonics of the Arcam, Wolfstan Dacs (and Saber dacs) really outperform the Burr Browns.
The preamp/amp is the central hub. AVM60 is a great preamp. Use 2x5325 amps ore 325 or 225 amps to your budget and configuration.
HDMI ARC from pre to TV, Oppo to HDMI pre input, all the other components onto the Pre and away you go.
Anthem is not a bit mover in Australia where Asian brands predominate to a price point. I took the Anthem over the Yamaha MX/CX combo for the flexibility and 13.2 channels.
That's my HT system. My stereo is another ballgame....