The image shows as example a small loop by car, recorded by two Garmin Dakota 10 devices. It seems both devices have had difficulties caused by the surrounding buildings, the "blue one" seemingly had better reception. A lot of the recorded coordinates seem to be more calculated/interpolated than measured.
We want to match the track to the (OSM) road network, and want to calculate driving speed. This proves difficult because of the scatter and interpolation. We would prefer missing over wrong positions.
Are other devices better suited for this task?
Additional info: One device was hold in the hand, the other one was laying by the window. WAAS off on both devices. This is in the middle of a longer tour, so the devices are already recording for more than an hour. We are "guest" on the cars, so mounting an external antenna is not an option.