You may wanna try a CD
Uploads make quite a big cost, and yes, servers go down (CW oxe/shop servers especially

)
Except for updated and new/transferred files of course, you should really have your .oxe's and keys backuped locally, let alone the OS software. And the OS (incl manuals) software is the only one that could be mirrored, .oxe's are generated through the CW server as you download them.
I have a mirror to
mod2, from OS v3.1, it'll stay there forever I think since my friend 'lost his password', and so did I eh :0