A real nice feature for those of us with experimentals would be a display of 'glide ratio'. This is a feature of the Garmin 2,3,496's that is a faster, easier way to find Best Glide speed. I believe the ratio is horizontal distance/vertical distance.
With that displayed, one would just vary the airspeed on one long glide until glide ratio is maximized. Note that airspeed...that's Best Glide Speed for that weight and wind condition.