I have stored 100+ megabyte files as tests and it works fine. It takes a long time to insert though. Thankfully you can queue them up using the download manager

I have stored 100+ megabyte files as tests and it works fine. It takes a long time to insert though. Thankfully you can queue them up using the download manager as you mention. A pirate bay like site on freenet could provide magnet links for those that want to torrent externally and also provide files for those that want to retrieve from freenet itself.