STI: prompt, courteous and efficient service
This franchise operates in the classic Lat Am way, using older cars. My Aveo had 70000kms on the odo. But, the STU airport Hertz team was efficient, helpful, and I was then able to extend my rental by one day from SDQ without hassle. Most importantly, there were no nasty gotchas when I returned, which is my #1 peeve (hate) about car rentals when it occurs.
I also rented from Adventure Rent A Car. Their one-way rate from STI to SDQ was much better than the big guys. Their facility is down the hill from STI arrivals but actually walkable (~1.5kms) if you don't have big cases to drag. The car was an Aveo also, with 50000kms, and some dents. This caused me angst at first, but there was no trouble or charge on dropoff. I did document with photos, as always, and ensured the management saw what I was doing. Also, one other point to note, their return under the Ava. de Americas bridge exit for SDQ is not the easiest to see/find.