The 90 is not more transparent than the AV10. The AV10 beats it in pretty much all metrics if you compared the test results here on ASR. The so called upgraded audio is based on marketing info that does not tell us what those so called/claimed better parts are. It is the same thing when Marantz claimed that have a mire musical and/or warm sound. It is all about a strategy, to create some reasons that would enhance the well understood Placebo effects or expectation bias among their fan base.
Marantz at least tell us about their volume ICs and OPA ICs, not just the DAC ICs. Anthem did ustilized a slighly better DAC but the ESS reference class dac in the AV10 is already at the extremely "transparent " level, a whopping 120 dB SINAD, vs Anthem's better IC spec'ed at 122 dB. Yet the AV10 measured a touch better, some would attribute that to implementation, that often may matter as much as or more so than the better IC can do.
As to the MP40, I have not seen comparable measurements, and not sure if Roomperfect would do better than ARCG, Audyssey and Dirac. It is not hard to do better than ARCG though, for use who don't want to spend time on post calibration manual tweaks.
On the objective side, DLBC and Audyssey with the app(s) are really good based on many actual measurements posted on forums, such as those measured with REW. For pure direct mode use, the AVM90 and the AV10 are practically equals. The AVM70 and 90 are more transparent for analog input sources, at least based on specs.
In terms of differences in transparancy between those gear, it is probably academic, because even -85 dB THD should be perceived transparent for humans, especially for those older than 40 who likely cannot hear much above 15 kHz. For those who could hear, may not perceived it as more transparent either.
EDIT: Keep in mind Anthem has been offering about 20% discount a few times a year, at USD 6,000, it becomes a lot more attractive.
