Depends what your use is, if it’s just for basic coms at events and runs then the short springer / stinger antennas are relatively inexpensive and flexible enough to take the impact from branches etc.
Ideally you want to mount it as high on the car as possible, for a series / Defender a light bar or gutter mount is ideal, but whatever you get and where’ve you mount it make sure you get the SWR checked and adjusted if required.
