Big Analytics Data add-on avoids sampled data by sending multiple requests to Google Analytics and then merge all the data into one report. 

The add-on calculates the optimal date range for minimum sampling. If necessary, it will send one request per day in the date range. If your report contains more than 10.000 rows of data, the add-on will send one request per 10.000 rows. 

Other handy features:
 - Combine multiple reports in one dataset
 - Create custom dimensions and metrics directly in the report configuration
 - Schedule reports, so that your data always is up to date.