This is your best bet for a 5 star experience in Princeville. Other than rain and a lot of it, our stay was perfect. As Platinum SPG members we were upgraded without even requesting it to a Prince Junior Suite, a beautiful room with a gorgeous bathroom and wonderful toiletries. A butler appeared and offered a lot of personal attention and made sure we knew we could request anything we needed help with. The lobby bar had different people performing at night and we enjoyed listening to them either before leaving or returning from dinner. We did not eat at Kauai Grill. They lost Fabrice, the former French chef, the menu is the most expensive on the island and the new executive chef is a gal from down at the very common Sheraton Poipu. We also read reviews where people said they felt hungry and the portions were on the small side, so it was an easy decision to skip. The pool service during the day was prompt and efficient. Pricey, as in $16 cocktails and $20 or so for the entree items during the lunch hour. We noticed a lot of older country club types soaking up the rays and were very entertained by the people watching. There also are a lot of Westin Time Share families that invade. Technically they are to use the beach and not the pool area, as the Westin doesn't have a beach. My thought is if they want to pay Westin prices let them use the Westin. So be cautioned. You will see a Westin time share bus that comes throughout the day dropping off and picking up time share families.
The Makena Terrace breakfast buffet is fine, nothing extraordinary, except for the price. And we did not partake in the Sunday brunch which is even more eye popping. Kauai in general is known for high food prices and not necessarily quality or bang that matches the buck, so I would encourage guests who have never visited before to buckle-up and smile whenever you sign the bill. The St Regis from what we could tell runs a few dollars more for every drink or food item, but that's what comes with staying at a 5 star resort.
The workout facility seems oddly located in a room off the lobby. There are plenty of cardio machines but little in the way of weight training machines. Everything is flawlessly maintained and in good working order, but no views. It feels like you're in a large closet.
Valet was quick and exceedingly pleasant. There are no resort fees at this property, so instead they hit the guest for $30/day parking. Given the room rates, this is absolutely absurd. For great views at sunset, rooms that are flawless, excellent service, this is the place to stay. Just be prepared to pay.