Strong request. Please keep all MP transaction records for now. Don't delete them the way you do in SL after 32 days. Reason is simple. We cannot get basic info from these records just yet, like who bought something.
I assume that later on, there will be a better viewer and ability to export CSVs and such from data so we can do our own processing. But until you get to that lower priority task, please keep all the records for us.