QFileSystemModel stylesheet conflict

[Alundra]

Hi all,
I have problem of conflict with stylesheet and QFileSystemModel arrows.
Is QFileSystemModel should be avoided to be used ? I read on different forums that it's deprecated like QDirModel.
The problem is when I go in a folder but it has no sub-folder and then if you close the parent and reopen, it's replaced by stylesheet.
I read that a custom QFileSystemModel can be faster than using the one in Qt ?
Is it possible to inherit QFileSystemModel to avoid this arrow and just use the QTreeView stylesheet ?
I already inherit QFileIconProvider to have custom folder icon.
Is it possible to have this folder icon in stylesheet ?
Thanks for the help