Not a bad approach. Minor nitpick to your hypothetical (lol) -- in this case one may want to use a 302 redirect since you might want to be consulted again for a

Not a bad approach. Minor nitpick to your hypothetical (lol) -- in this case one may want to use a 302 redirect since you might want to be consulted again for a subsequent download, rather than have your response cached (potentially on behalf of multiple users).