Agree. Both of mine are in the back, but if I had todo it over......
$250-300 for an optima, $50-100 for good cables, (I used welding cable, but the insulation doesn't last.) $50 for the shutoff, $100 for the relay to make the shutoff work right, (bought the wrong shut off, should have got the two circuit) battery box, etc.
The only advantage is the weight in the back of the car, if needed.