I use it for downloading songs from Seekpod, probably one of the most common uses for this SafariDL plugin.
When it comes to viewing the files locally, MobileFinder is only $1.99 in the appstore and is pretty feature rich given the heavy constraints its under.
If you're jailbroken, however, you can create a Symlink to the Downloads folder to view/listen to your files there, or just create a Playlist in vlc4iphone if you're downloading music and such as I am.
Creating a symlink is a chore through the terminal, and since Cyberduck doesn't offer it natively through a GUI, I chose to do it in WinSCP as shown below:
Just find your MobileFinder.app application folder in /var/mobile/Applications, then browse to the Documents folder inside of that folder with all the numbers. You're not browsing inside of the .app folder, the Documents folder is just outside.
Right Click > Create New > Link
Then Name the Symlink whatever you want in the top text field, and your target in the second text field is /var/mobile/Library/Downloads/
Here's what it looks like once you're all set:
Hope this helps