My issue is that it's a single file. If you have a network hiccup during that 5G download, have fun re-downloading it. I wish they offered torrents...
Edit: Just tried one of the files with curl. They resume just fine, and the download URLs aren't even tied to a session or IP. I copied the URL from my local browser and used curl on a remote server. No problem. :)
I guess a torrent might be tricky if they want to keep a "no redistribution" licensing clause.
Check out http://burnbit.com/
This specific site does support Range requests, therefore resuming - and most browsers can resume these days as well.