If Sony XM3s are like the XM2s (which I suspect they are) then not very good for the price, honestly.
I’ll argue to the death that you’re better off just playing some rain and using closed-ear headphones than paying for the ANC.
With Sony and Bose, here’s what you’re paying for on a $300 purchase:
$20 - headphone quality.
$1 - bluetooth adapter - often you can’t even connect to multiple devices at once. Garbage for a “premium” product on Sony’s end. Maybe Bose has it, but not sure.
$9 - mediocre software for EQ, etc.
$30 - for the good ANC. This stuff is useful for some people. I live in a city with crap infrastructure and a loud shaky train, and I never hear it when using my IEMs and V-Moda headphones. Also, if you have the ANC on and you’re not playing something. I’ve had Bose QC25s and Sony XM2s and this is my conclusion from using them for years. Personally, I have never been able to really block noise without also playing some type of audio on my headphones. I’ve always needed to add music, background rain sound (mynoise.net or the app) in order to really use it. As a reference, I do some Japanese studying (already around a high fluency level) on the train in the mornings, and I’m pretty anal about making sure I’m able to focus during reading or studying things, especially this moonrune language.
If I had to roughly break it down in terms of what matters and contributes to the noise blocking and focus…
Closed-Ear Headphones - 25%
ANC - 20%
Playing Rain/Audio - 55%. It depends on what type of noise you’re using, but I’ll recommend mynoise.net until I die. It’s the only natural sounding randomly generated rain that doesn’t distract me. Japanese Garden is especially lovely on there.
You can get earbuds or headphones that are full-featured and sound much better, just as portable, higher durability for under $100. I have the V-Moda M100s which are decent, much better than the Sony/Bose but not incredible, and they ran me $80 + $20 for the good new earpads from Amazon. My Chi-fi IEMs were $45 and sound better as well.
If you can score some XM2s for like $50-60 or something they’d be worth it for some bluetooth headphones to take on the train if you don’t have convenient to use IEMs or headphones already, but I wouldn’t pay anything more for them. Maybe if Sony and Bose can step their audio quality dramatically, add in some better quality bass and clarity, and then have it do a constant polling of audio at 10,000 times per second (0.0001ms polling) in order to truly cancel out outdoor sounds in real-time, that’d be very cool.