Just some tech I got from a local expert, he said dual antennas are only benificial if mounted minimal of 9' apart. He also told me long coax cables are generally for big rigs with a trailor. Its not better to have long cables but much easier to tune. With this info he also told me a 8' cables should work best for my setup with only one firestike.
We should do a simple test. It only take a min to swap out a cable. Have a buddy 1 mile away with a power meter and see which setup gets out better