I've had the DriveSmart 55 for several years and like the device. At this point, however, I'd like to upgrade to a larger screen. I'm stuck between the 66 and 76. Not sure if going up to the 66 will make much difference? It only picks up about 1/2" in diag screen size. However the 76 resolution is only 1024 x 600 compared to the 1280 x 720 on the other models. Will that matter? Can someone provide feedback on on these issues? Thanks...