I was out with my Tracker and mobile igate today. I missed some messages for Roger MW0IDX (but they arrived). I was also testing a mobile antenna. I tested it on a route that I drive regularly. The new simple 1/4 wave antenna on a mag mount outperformed my usual, much longer, dual-band “gain” antenna. Not really surprising.
I have mentioned before that many of the dual band antennas work poorly on 70cm. They may give a reasonable SWR, but any “gain” and radiation is not focussed towards the horizon.