Summary of my impressions
The latest XM3 true wireless (TW) from Sony is a great TW option for the audiophile. Compared to the Airpod Pro, the sound is more natural and realistic. The overall tone is closer to reference than consumer tuning. There is a little low mid warmth and plenty of sparkle on the top end but definitely not the V shaped consumer sound. ANC performance is good. Since this is an IEM, it won't have the performance of full size over ear, but it's more than enough for even classical music at moderate volume. Battery life is great - I got a solid 5 hours straight with ANC on my most recent flight. Definitely worth a try if you are looking for a TW solution. I will definitely try next generation models as I believe the technology will only get better.
My history of ANC Headphones
WH-1000X - Overall an OK solution. Sound was decent but low and high end were not very detailed. ANC was good. Worst part was pads did not breath so very warm on the ears.
WH-1000XM2 - Much better version across the board. However, for me the ANC created a negative pressure feeling in my ears that I don't like. Bose does the same thing. Pads still pretty warm and overall design still bulky compared to IEMs. I used these for about 3 months before deciding not for me because found myself reaching for my wired IEMs. Best version of WH series by far.
WH-1000XM3 - What a hot mess! Lower mids and bass elevated and muddy. I honestly thought my pair were broken until I read similar impressions. These were returned within a couple days. Have no idea What Sony was thinking. For those who want full size over ear find the XM2 version before they disappear!
Airpods Pro - Very impressive design. Still feels more ear bud than IEM so very comfortable. ANC reminds me of the negative pressure again. Sound is more consumer but well short of Beats consumer. Treble has sparkle and air but sounds pretty digital. Low end is not overly warm but not very defined either. It was only when my daughter asked for a pair, I decided just to give her mine and try the Sony and found a renewed one on Amazon for $150.
More details on WF-1000XM3
Like most IEMs, it took a lot of trial and error with ear tips to find a comfortable fit that sounds right. Airpod Pro definitely is superior in this regard. I ended up using the SS size silicon tips that came with my IER-Z1R. I'm pretty sure you want to insert these as far as they will go in the ear canals to get best isolation and sound. Unlike Airpod Pro, some of the sound isolation is passive so a deep, tight seal is required for XM3. Even with the right ear tips, it's still a bit of work to get these things in one's ears. Sony even has a diagram that shows how to insert and rotate for a tight seal. For those who have never used IEMs and don't like the feeling of the slight pressure, definitely go with Airpod Pro.
As far as connectivity goes, the Sony mobile app does more than Apple iOS for Airpod Pro. The big difference is system wide EQ in the Sony app, but it also has configurable ANC and other sound options. One of those options is the DSEE HX feature that is suppose to improve sound but I found it kills battery life by almost 50% so not worth it IMHO.
What I like best about the ANC feature is how natural it feels. I don't get the negative air pressure feeling and it seems to reduce more of the frequency spectrum than Airpod Pro which seems to focus more on lower. Based on some of the better passive isolating IEMs I've had that reduce about 26 dB, I'm guessing XM3 goes to about 35 dB or so which means it would reduce external noise by about another 50%. Definitely don't expect a tomb like silence.
Lastly, some may feel that AAC or SBC are not audiophile quality like LDAC or AptX. While true on paper, I find that Apple iOS does a very good job of optimizing AAC playback. I have not tried SBC, but using AAC all videos I tried - Youtube, Netflix, Amazon Prime Video play perfectly sync'd on my iPhone 11 Pro, iPad Pro, and Macbook Pro.