Audi is taking on Enterprise and Hertz with a rental service that delivers luxury cars to your door

I'm not in the market for a new car.

The next day, Charley returned (again, early) to pick up the car. The concierge service was my favorite part of Audi On Demand. Typically when I rent a car, I pay for Uber rides to and from the Enterprise office at the San Francisco airport. It costs upwards of $20 each way.

After a pleasurable day of driving down California's Highway 1, I returned delighted by my experience in the Q5. The car was comfortable, quiet, and handsomely styled.

Despite some early struggles making the reservation, Audi On Demand offered superior service and simplicity.

After a comprehensive review of the car's features, Charley left me with the Q5.

Audi On Demand is "as much about raising brand awareness as it is about offering a service," my colleague Bryan Logan, who reviewed the service in 2015, pointed out.

The automaker has long battled to outsell rivals Mercedes-Benz and BMW. As of September, Mercedez-Benz has sold 270,000 vehicles this year in the US. BMW and Audi trailed the top luxury automaker with 220,000 and 210,000 vehicles sold, respectively.

Audi On Demand lets potential customers drive its cars with little commitment and lots of flexibility. It might convince someone to stop by a dealership.

But the service isn't for everyone. The least-expensive rental through the service (the A4 sedan) costs $120 a day, which is about four times as much as an economy rental from Enterprise.

Heated seats? Yes, please.

My eyes darted from the display to the road with ease, but the interface gave more information than I needed. Icons for nearby destinations cluttered the screen.

(Later, we figured out how to change the display to a "Google Maps view" which more closely resembled the app's simple interface.)

When I'm following directions on Google Maps in my own car, I have to split my attention between the road and my phone in its cradle. In the Q5, the map appeared behind the steering wheel.

It was easier to write out my destination address than to use the standard knob to scroll through the alphabet and select characters one at a time, like in some Audi vehicles.

One of my favorite features was a touch pad in the center console.

The rental also included an Apple lightning cable.

The Q5 came equipped with CarPlay from Apple. It places the most popular iPhone functions on a big screen right in the center of a car's dashboard.

After connecting my phone via Bluetooth, I could play music from my Spotify playlists, load saved maps on Apple Maps, and even hear text messages read out loud using Siri voice control.

Charley pulled the Q5 right up to my door. As part of the concierge service, an Audi representative spends about 15 minutes showing customers around the car.

I've run into issues with rental car companies in the past when my vehicle hadn't been returned in time for my reservation. But my concierge, Charley, arrived 15 minutes early.

On a whim, I decided to check Audi On Demand's website. Oddly, the Q5 was not available through the app but it was through the website. I booked it before the option disappeared.

The Audi Q5 cost $190 a day, and I included all the extra insurance packages for an additional $25. By comparison, a luxury vehicle starts at $64 a day on Enterprise and $112 a day on Hertz.

After making my reservation, I got on with my morning routine.

In this case, no cars were available. It happened to be Fleet Week in San Francisco, which might have limited inventory with tourists coming in and locals escaping the chaos.

I was frustrated. Even after I picked my reservation date and time, the app still showed me all the vehicles — regardless of their availability. It seemed to me like a user-experience flaw.

Audi promises to deliver the vehicle to your door within two hours. But I quickly discovered that waiting until the last minute to book means that there are fewer cars available.

Most rental car companies let you choose a "vehicle class," like compact or full-size, but you might not know which car you're driving away with until you get to the pickup site.

Audi On Demand is more similar to Zipcar, which lets you choose a specific model of car.

Audi makes the reservation process simple by asking you to set your preferred reservation dates and times, choose pickup and drop-off locations, and select the vehicle you want to drive.

I was aiming to book a crossover for a trip to a pumpkin patch with friends later that day.

I downloaded the Audi On Demand app on my iPhone (if you have a Samsung you'll need to book through the website). And I was impressed by the variety of models to choose from.

I was excited to try Audi On Demand. I always thirsted to take my mom's Audi Q5 for a spin, and she never let me. It was "her other baby." But Audi was happy to lend me a car.

Audi is taking on Enterprise and Hertz with a rental service that delivers luxury cars to your door - here's what it's like

But I would use Audi On Demand again for a weekend getaway.