Be careful with this plugin. It will delete all your child sites on Multisite once it's turned on. No warnings, either.

This means that if you're already running multisite for a network, you'll certainly need a second multisite installation for demos.

The big issue is that this makes it difficult to demo the customer receiving a networked site.

Also, heads-up: you currently cannot use this plugin with sub-domained multisite installs. Only subdirectory.