Just to mention another file explorer, Solid Explorer is great especially becase it's easy to access Google Drive without having to use the Google drive interface.
I've been using FX File Explorer since 2012. It's straight up the best file manager on Android, especially when you use SMB and SFTP. Multi window makes moving things around easy as, and the built in text editor works a treat. Being able to share images from apps to FX's "Save As" option is awesome to. It means every app can save where you want.
No idea why it isn't more popular compared to the alternatives.
FX is one of the only 2 apps I ever paid for and it's great. I needed something to access SMB shares and it has always worked wonderfully. It's good for poking around in the file system on the phone too. There may be better stuff out since I bought it years ago but I've never had a reason to check.