Course it really depends which county you live in too...
I'm in Laurens county Technically... (by 10-20 yds) But if I were to pay the Gvle county taxes for my Truck... they would have been about $350 (348.xx iirc), Laurens is only $231.xx-
Also,being this close... both county auditors basically said I could "choose" my county (making sure I posted the same county on my returns too)

I also went legal and procured weighted tags instead of pulling trailers that would have consistantly put me over the guidelines for a "normal" auto tag. (one verbal warning was enough)
It seems the tag rates are the same where-ever you are.