Yes we all use gui software. I guess that results are good when you speak English and most top covers are in English, but when you are French like me, you want the French cover and this is clearly not the first one to go out, so you need to tweak your scrap.
All dune jukeboxes are creating a special folder with everything in it in a special format that the dune is able to read. This folder is based on each jukebox internal files, so differently to yamj it's not using general XML or nfo, but files that can be used only with the jukebox you chose. If you want to test another one you will need to rescrap everything, and of course do all your changes again. But most of the time, as those software are very easy to use and configure (yamj is a monster compared to it) you can test it with a small list of movies/series, see the one that fit your needs (they all have their strength and weaknesses) and stick with it forever.
On a purely visual point of view, DFI result on a dune is the exact same thing as eversion, except that all the tweaks you want to do can be done through a nice GUI and not by messing with nfo or cut/paste files in folders.