The trouble with hairstyles is they come and go with fashion and unless you know exactly what you want, stylists will cut it the way they want it in the latest fashion which doesn't suit everyone or every type of hair. He should take a pic of himself as Peter Bishop in season 1 or season 5, and tell them that's how he wants it.
Perhaps the stylists on The Affair will take it in hand when they start shooting, but if the wobbly beard was anything to go by he may be best to leave well alone.
