I feel I should echo filipedfs concerns about performance on large score in a separate post, as I have done a bit more experimenting since I wrote my comment on that thread, a comment that was perhaps a little too optimistic after all.
As I wanted to avoid any artifacts from xml import (artifacts which are far less numerous since the added improvements), I decided to write a quick “dummy” large orchestra file using the R command to extend the example to about 350 bars. At that point, the score is not really usable. Ctrl-A can take up to five minutes before being executed, and accessing menus once that is done can easily take the same amount of time. Inputting music, even in Galley view (which improves matters if the score is multi-flow) is extremely slow. I can share a dummy file with the team if they wish, but it is also very easy to create one from scratch using the method described above.