The ease of use is how I like it best, just add new items with no hassle at all! It does help me calculate what my print rates should be per job so that we can make an informed decision when requesting quotes from printers.
Not able to export previous data as Excel which would have been nice but this was not something i saw being advertised either during demo/tutorial time. Just keep adding jobs one by 1 until you've got enough information then compare your results against competitors prices (and their own) using price comparison sites such as Pricegrabber etc.