To reiterate what has already been said, as far as sound quality is concerned 99 vs 106 SINAD, I doubt very highly you would be have to tell the difference. (AVM90 not tested yet)
My opinion, you might be best served with the Marantz if debating the two. They are pretty evenly equally matched and I would be surprised if you could hear the difference between the two all things being equal. That being said, I would demo the heck out of both before I spent that much
Why Marantz:
- Slightly lower price point
- If you want DTS:X Pro
- More options for room correction Audyssey MultEQ XT32 w/ option to upgrade to Full DIRAC
- Easier learning curve than the Anthem ARC Genesis, ARC works great for me, but requires a lot more tweaking and it's debatable if Audyssey or Dirac are better The general consensus seems to be that they are from people on this site who have tested much more extensively than me. I have also had issues with my subs and ARC Genesis
- Should be less buggy, Anthem was plagued at the launch of the AVM70, but finding it now to be 99% bug free would assume the same for the AVM90
- On screen display vs using an App on tablet or Laptop (though I like this)
- If you use eARC Marantz seems to work a lot better, have had issues with my AMV70
- Supports up to 17.4 (though only 15.4 speakers support processing)
- Sevice/Repair centers, they have quite a few that are US based, vs having to send into Canada
I have owned a few Marantz Pre/Pros and never really had issues with any, though in my experience on their other gear like their Blu-ray players (a while back) I found customer support terrible. I have always received excellent support from Anthem/Paradigm.
I will add, I am happy with my AVM70, it sounds great, have managed to work through the bugs, and I love the way it looks/performs. I am equally happy with my Marantz integrated 40n. If the build quality of the AV10 is on the same level as the 40n, you will be completely happy.