We use MS project for tracking the precision of our estimates but we use Excel to do the actual calculations. In Excel, we store the attributes and their value based on an adjusted value factor, then the tally of all attributes is converted into effort. This effort is added to MS project schedules in a column that we then compare with the actual work when the task is completed. to track, we plug into Project server’s SQL database and pull out a pivot table that gives us the difference per WBS (another category asigned to each task).
I think the main purpose of MS Project is to track what you plan. Planning alone serves no purpose.