OK, after a few more days of using the XM4 and going for a walk today, here are some more observations and thoughts (I know most everything I am saying has probably already been said... LOL)
First off, I am glad I bought these even if I end up selling them...
Sony definitely made a great sounding TWS, I honestly did not expect them to sound this good. I expected them to be dark and lacking in detail enough that I would be reaching for something else. Out of the box they mostly are exactly that. But to my surprise the drivers respond exceptionally well to the EQ, opening up the vocals so they are expressive with decent emotion, the treble lacks just a bit of airiness but not by much and manages instruments like cymbals well. Bass is also tighter and more detailed than I expected.
I also love how well these isolate even without ANC, I actually only need to enable ANC in certain situations, which is great! When I do enable ANC these really are the most isolating TWS I have tried.
Now for my gripes...
Comfort - I really wish the design did not have that darn bump at the bottom of the antenna thing. If they had just made it round like they did on the Linkbuds S the bottom of my ear would not be getting so sore! The size of these is just a bit too big for my average size concha. They don't need to be Linkbuds S small, but a bit smaller would be nice. Throw the darn foam tips away, or just include the good old Hybrid tips along with them so people have a choice.
Stability - These really are unstable in my ear, working loose even just sitting and really work loose the moment I start walking. As such they will never work as a workout TWS which is a pity since they have a signature that would be awesome in the gym or when going for a run.
Ambient Mode - this mode works but just barely... The positive is does not affact sound quality. The negative is once music is playing even at low volume, I cannot hear people talking to me which would be important in the office and when at home with my family, or when on busy streets where I need to pay attention to traffics etc.)
I am a FICKLE person... The gripes have me on the fence on whether I will keep these. I am going to see if the comfort one in particular improves with more use (can my ears get used to wearing these...). I also need much better ambient mode functionality.
If the WF-1000XM5 manages to be smaller (does not have to be Linkbuds S small), remove un-necessary bumps in its shape, improve ambient mode, maintain passive and ANC levels, have a similar battery life level, and have the same or better audio detail retrieval I would be quite interested in them and might be enticed to pay retail versus waiting another 2 years when the prices started to fall more before giving them a try.