We never pre-book transfers.
SNA is a small airport and easy to get through.
Once off the plane we head right out past baggage claim to the taxi zone. There is a taxi director, they get you the next available taxi.
When I have 5 in my group we ask for a mini-van taxi. There is plenty of room for everyone and their luggage plus backpacks.
In October the taxi fair from SNA to PPH was $45.
Geemo is spot on. Get a cab, ask for a flat rate. Like geemo said, it should be about $45 plus tip no matter if it is a car or mini van. No extra stops, no waiting, no hassle!