Just read through this thread and would really like to advocate for "Tick/Untick Selected Files" as a menu option, along with Selecting Ticked.
Say I'm going though a BIG pile of duplicates, and I think that all the MP3s now exist in FLAC, but I want to be sure. This is what I would do:
- Sort by extension
- Select all MP3s
- Tick selected
- Resort by Artist/Title
- Select ticked
- Unselect any that don't appear to have FLAC duplicates
- Delete the rest
(On the other hand, steps 3 & 5 would be eliminated completely if the selected files stayed selected when they were resorted...)