Easy Blog Networks already take care of backup so there's no need to install such plugins. You can download your blog's backup (database and WordPress files) with just a click on the blog's info page.
We block the most common migration plugin since they're known to cause issues - breaks WordPress tables and conflict with our core plugin.
We have an automatic transfer process you can use for moving blogs over to the EBN servers.
Please note though that import within EBN servers is not possible for various reasons, the three most common reasons are 1. we highly discourage re-using a deindexed blog content to a new domain, 2. duplicate content is a bad, bad idea, and 3) system blocks zip upload/download.
We also have a simplified working process for moving blogs to a different hosting provider.