Refresh times and resource use are nothing to write home about but 1Tree interface is clean, simple and easy to understand. Settings are kept in a '1Tree.exe.config' file in the program folder (stealth status unchecked!).
1Tree loads your local and network drives, folders and files with their sizes (sorted by size in descending order), and provides you with the common commands (e.g. Delete, Move to, Rename) and a few special commands (e.g. Get Full Path of Resource) for drives/files/folders. So, with 1Tree Basic, you can do the manual disk cleaning work easily.
Download 1Tree Basic latest release (currently v6.0) from https://1tree.info/basic.htm.