Apart from having to call the US ans spending £20 on calls to confirm my pick up the service was faultless. We also had to pay for the vehicles airport parking tax?
Our driver was at the airport when our plane landed and was ready to go when we were. No problems at all!
The booking details in the email told me to confirm the reservation 24 hours in advance by phone. For some reason i was not able to get through on the phone number given (problem with my mobile) so i went to the email and sent a message via the companies website stating that i was unable to call by phone, i gave them the flight arrival times and my reservation details and also my email address.
On arrival in Nashville, i had heard nothing via email so actually managed to get through to the number. They were aware of my reservation, but said it had not been confirmed and they had to call another company to try and sort it out.
Eventually after several calls the car did pick us up to take us downtown to our hotel, but it did take quite a bit of time and i have to say, it was stress we didn't need!
I also booked transport from Chicago airport to downtown for a few days before with another Company which was hassle free and did not require confirmation via phone...and they were waiting for me on arrival. Unfortunately, this company did not operate in Nashville, otherwise i would have used them.
Will use Viator for trips et again....but definitely not for airport transfers.