Readings done via email are literally emailed to you. The email reading is equivalent to a phone or in-person reading and will provide you with as much, if not, more information than the other readings. The email reading reads like a transcript. Everything I would have verbalized to you is typed into a document and then emailed to you.
Readings done via email may provide more information than you would get from phone or in person readings because there are no time constraints. Any and all information that comes to me is typed for you. When I feel the reading is complete, I save it and email it along. For more information, please see my FAQ above.