How much load will your live connections be? I would say 'LIVE' connection is always highly depended on how well your source db performance does. e.g. how many concurrent session allowed in db and how fast is your csql returns.
So in your situation, my opinions is if number of live connections is less then 24 (hourly refresh in a day will be 24 times), and each time the rendering time for each workbook is excepted. Then LIVE might be better else I would definitely suggest 'Extracts'.