Sync isn't working for me still. Same as 109. Still have the Insider startup page. God knows why MS want to hard code this into it. Really liking it though despite these minor quips.
Just remove one dot before '\User Data' and your data will be stored in the correct folder. The line will be: D:\Apps\Edge\MSEdge.exe --user-data-dir=".\User Data"
I have not installed any extension from that page, I have installed all my extensions (12) from the Chrome web store.
In the new version, the favorites bar works as it should be, that is, if the toggle to "Show favorites bar" is disable, that bar continues to appear in the NTP, as it works in the "old" Edge and in other browsers such as Chrome .