Feedback about this update
Strangely this time, I was not told to update first through the Store, so MSFS started with a 17 Gb update of 1.14.6.0, I did not understand why. Anyway, did it, and cleaned BTW the Community folder at that time
I went then in the Windows Store and requested the updates, it showed for MSFS and performed the store update at that time
Then I restarted MSFS and this time, I was invited to start the 1.15.7.0 update for about 16 Gb
Everything Ok with the update procedure, fast and flawless
Sim then started, I stopped it and restarted it to be safe
I did WU4 in the MarketPlace, and everything was fine too.
I noticed the previous bug seen in WU3 with packages updates (see Content Manager Freezes) was fixed, no more content manager freeze 
I flew several places like over Paris, Lyon, and these areas, performances are great!
Paris gets better FPS than London.
Paris area is great and very realistic with PG on
Something that could be improved is the loading time and rendering of PG when flying
Note I am on High settings, I don’t know if something can be done to improve further the overall PG in dense city areas, but correct anyway above 1000ft
I use a 16Gb rolling cache, to help a bit with that