If this is checked, EagleFiler will use Quick Look rather than its own e-mail engine to display messages in the record viewer.
The advantages of EagleFiler’s engine are that it is faster, it lets you control the fonts and colors, you can select and copy text, search matches are highlighted, and you can use the Find panel. It can also display remote images.
The advantages of the Quick Look engine are that it can display images that are attached to the message (both engines can display remote images that are referenced by URL) and in some cases it has better HTML rendering. A future version of EagleFiler’s engine will incorporate these features so that it’s not necessary to use Quick Look.
See also: Message ‣ Plain Text and Message ‣ Rich Text, the Importing Mail section.
The Use Quick Look option is not available in the Mac App Store version of EagleFiler.