No essay on FSI repacks would be useful without addressing their limitations:
Understanding the source helps you prepare: fsi comics repack
A raw FSI folder for a 32-page comic contains 32+ image files plus metadata. A repack condenses these into a single file (.cbz or .cbr). Imagine managing 500 comics as 500 files versus 16,000 loose images. No essay on FSI repacks would be useful
For those using tablets (iPad, Android), you might want more than .cbz. fsi comics repack