manker: The days that scene content was uploaded by persons who got the files from usenet are long gone. It's not humans, it's scripts who upload scene content. The whole process is automated and the files come directly from scene sites.
There's no manual work involved, that's why it's so ineffective to let thousand users run a process that can be done once by a script in a matter of seconds. The combined HD Space that can be saved by millions of users is huge if all torrent sites dump rars. That's literally millions of dollars that can be saved.
It's hard to find pros at all.
Con: Rar files are hardly archived by the common user but deleted. Unpacked content is more likely to be kept and seeded and therefore offers better torrent retention
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