It depends on how many nights you are staying. We stayed nine nights, and I'm so happy we had a car. The first three nights you can stay exclusively at Aulani and be fine. For our family of four (two parents, an eleven-year-old, and a four-year-old), having a vehicle was fantastic. We could go off-property for food (Costco and organic grocery). We also are big Disney World visitors, so the slow pace eventually got to us. When we explored the island, we had so many cool, random encounters. It is so nice to have a car, and if you're using DVC, there is no charge for parking.