I would take a taxi over a hotel car. The reason is simple: the last time I got a hotel car to pick me up at MEX, we had to traipse into the parking garage. It was a waste of time, especially since the taxis are waiting for you to get in and go.

Especially if if you’re arriving late at night, the ride to Polanco should be under 30 minutes, so long as traffic is merciful (and it often isn’t).

Have a great trip!