Think of it this way - if you owned an AMP, what would you value in a customer? Looks is going to be way down the list. I would say that they look for -
1. Safety - the customer is not LE or a criminal
2. Safety for the girls - the customer is not abusive
3. Reliable - the customer doesn't show up late and expect them to accommodate, and doesn't cancel appointments last minute. Also, there are no issues with payment.
4. Attitude - the customer puts the girl at ease and doesn't cause problems, like demanding BBFS or something like that
If you are strong with these 4, then they will want you to be happy and give you good service. They want you to come back. The manager will want the girl to take care of you. Frankly, with the risks of their business, getting and keeping a good customer is very important to them. I mean, do you think an AMP prefers a fat ugly guy who passes all 4 criteria above, or a really hot guy who gets mad at the girl if she doesn't do greek?
This is why the top AMPs like PH pretty much always provide top notch service and it's such a surprise when it's not good. That same service is provided to everyone, and we all vary in our looks. Also, you will notice that we will see multiple bad reviews from the same girl...I guarantee some of the customers are pretty decent looking but still get that bad performance.
Now, if you have two guys, one hot and one ugly, who meet all 4 criteria above, does the hot guy get better service? Maaaaybe....if the girl is new to the business and hasn't done 100's of guys yet. But otherwise, I'm pretty sure they're both going to get about the same service because in both cases, the AMP wants to keep the customer.