Honestly with the way that the inventory at Hertz has been since I started with them in the last year - 'best' for me tends to be whichever vehicle is least beat to .....
Oftentimes for me that means I would rather take a Camry with few miles on it rather than a loaded Cadillac or BMW with 50,000 plus miles and bad wheel bearings.
Many of the vehicles in the inventory have many, many miles and in some serious need of maintenance.