There are to many free programs that do the same thing or more, TreeSize, WizTree, WinDirStat, etc.

I'm going to give my observations from trying 1Tree Pro this morning in the form of suggestions from the author.
Some I may get wrong, some may be functions the program has that I didn't find, apologies.
Also I hope others may comment programs they know of that do better in these areas.

1. Add a "Stop" function. After 6 minutes I gave up and had to end the program to get it to stop building the tree for an Easystore drive. I'm assuming it would have got there eventually, but just wanted the top level directory sizes.

2. Allow an easy selection of how many levels to gather for a new drive.

3. Populate the display of the first level as quickly as you can, then continue to gather the lower levels that won't initially be displayed. Very helpful with large drives (and they are only getting larger).

4. An estimate of how long an operation is going to take would be handy. Similar to windows telling you how long to finish copying the remaining files.

5. Why a warning when I select a top level drive ? Not obvious.

6. Add a highlight to select function, that allows more than one line to be selected. Similar to windows, click left mouse button, drag while holding the button to highlight additional. Or at least Click first selection, hold shift, click last selection, which highlights all items in between. Make copy to clipboard hold these and then tree becomes printable. As it stands now we have to manually select all tree entries (maybe hundreds) and their copy path to clipboard. Copy selected tree level to clipboard would be helpful.

6. Add a "Print" function. To print selected lines.

7. Windows OneDrive content tree is shown, but not identified by name as to where that tree section came from. Took a while to figure out it was showing sections of OneDrive as a separate unidentified area.

I do a lot of photography. My biggest challenge is finding where an event is located in archive drives. For instance I setup the drive folders by year, month, event, and the actual image files. i.e. a path might look like F:\2022\March\Ren Fair1\_BGA9023.NEF (name of image as it came off camera). If I can easily build a list showing the content of each month down to the event level only, I can save is as a text file at the year level. I can also print it and place the list with offline drives, and create a master list on the computer. Can't find a way to do this with today's offering as it seems to function currently. Anyone know of any program that can do this easily ? Thanks.

1. I've used Folder Size from RoteBetaSoftware to do this. 1TreePro is slower. On my C:\ drive, which is an SSD, 1TreePro took 1.5 minutes longer to scan it.
2. There's no way to cancel the scan once it starts. Folder Size allows you to cancel.

Since a long time I've been using two softwares for this purpose:
1)Q-Dir (the quad file manager of SoftwareOK). It is free and lightweight.
2) XYPlorer (dual panel file manager). It is not free but nice one.
I did not try this (1Tree Pro 8.0) yet. If you tried please share your experience. How is it?

What advantages does this have over the free WinDirStat?

TreeSize Free is a Freeware Program that does the same thing.