Sending a Grab for a girl
I was in Manila in September and I sent Grab several times to pick up the girl. The communication between you and the girl must be up to the minute though. Sometimes the address she gives you doesn't show on the app and can be a few blocks away from the nearest pickup spot. You have to settle on a pickup spot with her before you book.
Girls running late: The Grab driver usually won't wait more than a minute so you have to make sure that she is there. You can share the driver's details with her.
Even with all this, twice the Grab guy took off and I was charged a cancellation fee. Its 50 pesos and you'll pay next time you use a Grab car. Assuming you use cash. I haven't been able to use my US credit card on my Grag account. All in all, I like the option of sending the car because often these girls don't have a nickel in their pocket.