I just want to add that we have a tool MetaVis Migrator for SharePoint that can help you to copy site collections. You can copy there the whole site collections or you can copy granularly individual sites, lists, libraries, content types, fields, individual items and documents with versions and metadata, groups, users and permissions, WEB Part Pages with WEB Parts, list views, term stores with term sets, certain look and feel and navigation settings and some SharePoint Designer customizations. It can copy data from SharePoint 2003, 2007 or 2010 sites, from file systems and Exchange public folders, preserves created and modified times and users, looks like Windows Explorer with drag and drop and copy / paste capabilities.
We have 15 days free trial. If you have Office 365 account you can download the product and give it a try. http://www.metavistech.com
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