MX4 and 5 have reports that can be run by User and/or Device. I have merchants that require this feature to run their business and determine where payments are coming from. Can't turn off 4/5 without this feature in 6.
Great news! The user report is now available for all MXM accounts. To access this report simply click on Reports in the left-hand menu. Under the Base reports, you will see "User Report" as the last report on the list.
This report has a summary at the top to break down the performance of each user to show their transaction count as well as the sum for all transactions. Below that is a list of all transactions. Use the search box to view payments for a specific user (don't forget to click enter on your keyboard to search) or look up a specific reference number. The filter lets you narrow down on the date or range in question. Not to mention you can export!
I have attached a screenshot for where to find this awesome new report, but go check it out for yourself and see how many payments your users are making.