So the Maxx showed up yesterday. I'm impressed. I think people who purchase them will be very happy.
$600 with tax is a lot, but the build quality is impeccable and you pay a premium for how slick all the (cr)apple stuff works together. Switching from listening to a podcast on my phone to a YouTube video on the iPad to a work zoom call on the MacBook without pressing a single button is a neat trick.
As for sound quality I think it meets expectations. It will not blow anyone on HC away with how good it sounds, but I also think it won't offend either. The tuning is fairly neutral, which is appreciated. Beats by Steve Jobs™ with a warmed-over bass-boosted response they are not, and that makes me glad.
I'm not a lover of closed headphones when open headphones are an option. The usual closed headphone characteristics are all present in the Maxx.
These are not a replacement for a proper headphone rig. My HD800S aren't going anywhere. My HD800S also aren't able to operate without being tethered to my ECP amps, which is where the Maxx come in. If you want to listen to something while walking around the house or the office or on the airplane then these will hit the spot. Their mass is such that I don't think they would be a good fit for exercising.