Google Maps application, use Data API or my own data store

I wish to develop a site mashing up user generated g开发者_StackOverflow中文版eodata content with geodatacontent from Google search (Locations of niche businesses entered and recommend/commented by the users as well as the search result though Google Maps for the same businesses, presented on a map. Users can grade/comment on the Google Search result as well, I store the comments and grades etc.)

Any tips as to whether try to use the Data API or just keep all the data in my own datastore?