Not noticeably in most cases. Omniscope views and report pages look pretty much the same regardless of record count, and only the very largest data sets (over about 15 million cells) need testing for possible performance optimisation. You can mock-up your target data set in a spreadsheet, open it in Omniscope and develop a full set of reports in a day. Omniscope is a very quick way to put sample (or even real) reports on user desks practically the next day, surfacing all sorts of issues of data quality, interpretation, ownership, etc. while the reporting database, warehouse or 'mart' is still being designed.