For me TotalCommander
is the best file manager. For a long time I am using two window file manager also on my regular PCs. Moving files around can't get any easier. It offers drag&drop, dealing with zip files, built-in text editor, bookmarks, yadayadayada .... TotalCommander also has a bunch of extensions to help with LAN connections, FTP, WebDAV and more. For instance, my ownCloud system is connected via WebDAV.
For me, TotalCommander is the one-stop solution for everything file related. Maybe some of you would like to give it a try.
Samsung Galaxy S4 - GT-I9505 Stock I9505XXUFNB8 | KK4.4.2 | v3.4.0-481100
Asus Transformer TF700 - CROMBi-kk 20140517 | KitKat 4.4.2 | 3.1.10-10.6.1.14.10 that9-oc
Nook Color - CM11 | JB 4.4 | 3.0.8-g78e81af