I started using my X two weeks ago. As always, I did not import the iCloud backup from my 6 and set it up as a new phone. By now, I am using about 20gb.
I used my 6 128gb since 2014, much stuff piled up in three years (mostly photos and downloaded playlists from music streaming services) and by the end I was using about 80gb. Since I plan to keep the X for at least the same amount of time as my 6 (I upgrade only when there is a complete redesign), I went for the 256gb version. With better cameras and higher resolution online content, I expect it to be more future proof.
I used my 6 128gb since 2014, much stuff piled up in three years (mostly photos and downloaded playlists from music streaming services) and by the end I was using about 80gb. Since I plan to keep the X for at least the same amount of time as my 6 (I upgrade only when there is a complete redesign), I went for the 256gb version. With better cameras and higher resolution online content, I expect it to be more future proof.