For anyone considering either headphones: I've used both extensively, have a strong audio / DSP background, and have not been paid by either manufacturer. Here's a comparative review, with a focus on ANC and audio performance.

MECHANICAL BUILD

The Bose are built significantly better than the Sony. Sturdier frame / hinges, simpler overall construction (a good thing!). Stronger materials used in places (metal). Wider frame too, so feel more stable on the head. Winner: Bose.

EAR PADS

The Bose have thicker earpads, ears do not touch the mesh (which they do for me with the Sony). Probably also less sweating problems, feel slightly cooler overall. Material also seems more durable / "premium". Winner: Bose.

ANC

Bose's ANC is much fussier. Initiates a long calibration phase (think 5 to 10 seconds) every time there's a significant change of "head fit" (often triggered even by normal body movements / walking / facial expressions), during which the ANC drops out and only gradually returns. Sony has this too, but only as an ADDITIONAL, special "Turbo ANC" mode that OPTIONALLY kicks in during high ambient noise levels. Otherwise, the "default" ANC is on all the time and completely independent of fit or movement, and is "good enough" for 99% of use cases. Overall, when the Bose are left alone and the user is sitting still, the ANC is as good as the Sony in "Turbo ANC" mode. Winner: Sony, mostly due to less "fussiness".

SOUND

Both headphones need a lot of EQ (provided through the apps) to sound even remotely neutral, but after EQ, both sound good. The Bose might sound a bit more detailed both in the bass and treble ranges (I could detect mistakes in some of my productions that I hadn't noticed before). So, this would almost be a tie -- HOWEVER, the Bose have a problem that the Sony don't have: There's a very noticeable background noise (a bit between white and pink noise on the spectrum -- roughly centered around 2 kHz, 1 kHz wide), even when ANC is turned off via the app. This is either "by design" (why?) or due to noisy DACs. It's about as loud as being in the middle of a forest on a slightly windy (say, 15 km/h sustained) day. This obviously is a problem both for "drifting away" in ANC mode and for listening to quiet passages of music. So, despite the Bose's slightly more detailed sound, the noise floor makes the Sony the clear winner.

FIRMWARE / BLUETOOTH

The firmware on the Bose is a bit buggy. Sometimes, it won't react to button presses / long-presses to turn them on / off, and one has to try multiple times. Bluetooth support seems better on the Sony -- more Codecs (LDAC), more stable overall.

USABILITY

The actions of the hardware buttons make more sense on the Sony. One of the most important actions -- switching ANC on and off -- is a long-press on the Bose, but a normal press on the Sony. Also, querying the battery state is a normal press on the Sony, but an awkward "touch the volume strip at exactly the right spot and for the right duration" action on the Bose. Winner: Sony.

APPS

Both apps are pretty solid, however the Bose app allows slightly more configuration, including fine-tuning the ANC amount, which Sony doesn't seem to offer. I'd give Bose a slight win here.

MICROPHONE

I did not test the microphone on the Bose, so I can't compare.