Antenna Location

My old Tracker Scout, with a Lencom tapped antenna (1.8m), always ran exceptionally well off the bullbar. I did move it to a rear spare wheel mount at one stage and it was just as good there. I should imagine that roof centre, with a very good ground connection would be the best, but that's impractical with taps - too heavy - too high - too awkward to get to. The tapped antenna system is so efficient it seems (compared to thecompromisedauto-tunes) that you'll boom out from any location on the vehicle in my view (if the radio and antenna are in good nick). At least you can see it at the front - a good tap is quite expensive to repair or replace if smashed on a tree.

Grumpy, the most effecient place is on the bullbar. But thats not the whole story. Although up to 9 db difference has been measured between the front and back at times, it also depends upon the frequency. Basically you won't notice that much difference.
Yes you can see it on the front, but will your insurance company cover you if a human emu jumps in front ? Not sure if current road regs allow a whip at front, I know autotunes have to be at the back. (policing of this is different in different places).

GB,

From my experience, bullbar is best, considering you need to change the tap cable regularly. And as already mentioned, it is handy to be able to "see" the aerial. Lot of loot to damage on a low hanging gidgea branch.

Hooroo...