On the Airbus 320 we clean up the flight plan to delete any unused waypoints. We do this generally as we pass over or abeam them or it is clear we won't be going near them when the controller has given us a heading to fly. Then when we have a fair idea that we will get vectors for base or onto an intercept heading for the final approach course we will clean up the entire flight plan by going direct to the centre fix shown in the plan and checking that the radial is the extended centre line of the runway. This gives a nice picture to help with your situational awareness and particularly at airports with parallel approaches is a good reference to ensure you don't go blasting through the localiser course. You also need to pull heading so that it doesn't go into NAV mode and voila the track miles should be more representative. Also I usually have the runway in the progress page so that it gives me distance to the threshold as a further check and I flick between the flight plan and progress pages to keep an eye on my distance. Usually you will also have a DME as a further backup on the ND as well.