There is reason in the corporate world for a private blockchain, mainly for privacy reasons, but mijin offers higher transaction speed along with lower costs, as they pay a subscription rather than paying fees that compound up, of course for smaller businesses, NEM works out much cheaper, so its all relative to its use.

Both chains use the same API's so switching between is not hard, it also demonstrates the technology behind NEM, since Mijin is based on NEM technology.

In other words, we have the best of both worlds!