Randy, the tech I spoke to said to get the 2 antennas 10' apart. That doesn't seem reasonable since these are made to use in a car. I found success at about 6 to 7'. I'm sure it has a lot to do with the composition of the roof and such. And yes, I am having the greatest success with the stock antennas that came with the unit. I think they recommend the Trucker/RV antenna due to the fact most RV roofs aren't metal and it doesn't require a ground plane. The ground plane issue is easily overcome to use the magnet mount antenna.....