Just got 10 on my TMO this morning.
I waited a couple days until I had enough time to spare for an update. I don't like doing it over night because it means charging my phone overnight.
Initial thoughts:
1) all the animations seems to be much smoother. I use a 3rd party launcher and on pie it ran very snappy with very little animation making it feel jerky at times. Now it's very smooth. Apple like in a way with the way the multi-task page kinda smoothly floats around the page.
2) the settings page has been completely revamped. Gone is the 4 category horizonalty divided sections and now it's one long scrolling page divided neatly into sub categories.
3) there are very few icon packs on the LG smartworld that are compatible with Android 10. I use lawnchair so I was able to play around in there but for anyone who wants to use the default launcher it may be an inconvenience.
4) gesture controls on A10 are really cool but because I prefer to use lawnchair (I need that scrolling app drawer! Like come on LG, it's so much better!) the gestures were rather janky. Maybe they'd smoothen out if I used it more (when I test drives then with the LG launcher it took a bit of time and a reset for then to go smoothly idk why but twas so) but I stuck to the android pie gestures which are still supported and they even added reversing the back button to the right side of the bar, which is helpful cuz I'm a righty. I'm glad that they're still there along with 3 button nav for those who like it.
5) I love the new privacy settings for location permissions.
6) digital wellbeing is here for LG phones. I haven't used it yet but it looks intriguing.
That's it so far I'll update y'all when other stuff pop up