Flikr URL for Featured Image

Here is a plugin that appears to do exactly what I need:

http://epicplugins.com/external-url-link-to-featured-images/

Can you please tell me which of the two options below that the DW Focus Theme would require:

“20 APRIL 2013 UPDATE: THIS PLUGIN NOW ALLOWS YOU TO USE EXTERNAL LINKS WITHOUT TRANSFERRING TO YOUR OWN SERVER

The plugin has been updated with an additional option. It allows you to set your post thumbnail (featured image) from an external URL without uploading the image to your WordPress media library.

Note this only works if your theme uses the get_the_post_thumbnail(); function in its coding. The plugin now has two options:-

1. Set featured image from external URL – uses a filter to replace the output of get_the_post_thumbnail (may not work in all themes that write their own function for displaying post thumbnails). The file remains on the external server location.
2. Upload image from external URL and set as featured image. This uploads the external image to your media library and attaches it to your post as the featured image (this may be better for display if linking to large images as they will be crunched by the WordPress image crunching routine). The file will be copied and stored on your own server.

Depending on your theme design and image display preference you can choose which one you wish to use through the use of this plugin.”