We were more than satisfied with the entire process.

Booked on-line in advance.

On arrival there was a short (10 minute) queue at the Hertz desk despite several flights arriving. The desk clerk was helpful, cheerful and there was no hard sell for extra insurance or any other extras. Yes they were mentioned but not pushed, maybe I have a face that just says "don't ask". I did pay for the fuel in advance, Hertz charged me $59 and I have found the tank from warning light on took a $50 refill, so given the reserve a little more expensive but not a rip off.

The car we ordered was both available and sitting in the airport parking garage, in fact in the parking slot nearest to the elevator. It was clean and had about 4000 miles on the clock.

Minor glitch occured after week one, warning lights on the dash. Phone Hertz airport number and was asked to return it to the airport for a replacement. Bit of a pain due to journey time and toll costs, but we did drive away with another full tank so no complaints. Swapping the car took about 10 minutes at the Hertz customer service booth in the garage. 

I have even found that Hertz returned some money to my credit card as the cost at time of pick-up was less that the quote cost at time of booking.

 I do use car rental a lot in the UK for business and this wasn't any better or worse apart from the warning light glitch it was totally unremarkable and that is really what you want the vacation car rental process to be.

So I would definately use Hertz at Orlando International again, totally professional.