Will Migrating Content Between Sites Preserve CKEditor Styles?
Yes, as long as you keep your database integrity when migrating. 

CKEditor basically adds HTML tags and attributes to your data, which are saved in your fields' tables in the database. So, for example, if you have a body field that contains  text formatted like "Hello, body", and take a look at your field_data_body table, you will see something like this:

&lt;p&gt;Hello, &lt;strong&gt;body&lt;/strong&gt;...