Sorry, I just re-read this ticket and see it's about delays when copying stuff (somehow I got it in my head that it was grinding to almost a halt during scanning).
Could be something in your AppData is open/locked & requires use of Windows VSS to try and copy it, which is running extremely slowly / grinding to a halt.
But for sake of good order / previous
/ re-testing as near like-for-like as I can, I ran a test to copy my entire C drive to a partition on the mechanical drive. This was about 144,000 files, 29GB and took about 43 mins (because of the number of files, not the number of GB).
FYG, my SSD is OCZ-VERTEX4, total 237GB (formatted), 50GB used (note that I used default Filters, so no copy of swap files, etc, hence only 29GB copied)
All ...\users\AppData folders were included, and seemed to make no difference. A few expected Access Denied errors (about 30), otherwise no issues.
Anyhow, glad to hear it seems to be working better for you without
Could be something in your AppData is open/locked & requires use of Windows VSS to try and copy it, which is running extremely slowly / grinding to a halt.
But for sake of good order / previous

FYG, my SSD is OCZ-VERTEX4, total 237GB (formatted), 50GB used (note that I used default Filters, so no copy of swap files, etc, hence only 29GB copied)
All ...\users\AppData folders were included, and seemed to make no difference. A few expected Access Denied errors (about 30), otherwise no issues.
Anyhow, glad to hear it seems to be working better for you without
