I've stayed at both the Hilton and the WA.

Room:
Hilton: Basic, minor upgrade from partial oceanview to ocean view, small balcony, dated bathroom shutters which open into the bedroom area. Large buildings with hundreds of units in a row across many floors.
WA: Obviously you've seen the photos, but a hacienda type decor. Large outdoor patio/deck with private plunge pool. This is a highlight for the stay. Large bathroom with soaking tub, shower and double sinks. Good storage. A variety of buildings and styles, many no taller than three stories. More of a boutique feel but the grounds don't feel overly compact.

Service:
Hilton: Only one team member was exceptional. All other service was basic/non-memorable.
WA: Just about every interaction feels memorable. Genuine and warm service. You'll see bell services team member stop his cart because he sees a room service dish left outside a door. Not his job right? Doesn't matter- they take ownership.

Breakfast:
Hilton: Super chaotic self-service buffet. Larger than WA but nothing memorable
WA: Small selection and $10 cost to upgrade, but my family (Mexican American) found the food to be incredible. Can't wait to get back for the homemade corn tortillas.

Location
Hilton: in the Corridor, between Cabo and San Jose del Cabo. Nothing walkable nearby. But great location to go into either city by Uber. Gallery area of San Jose is great. Love Flora Farms just outside of San Jose. The ocean CAN be swimmable here, sometimes. You can at least dip your toes in.
WA: Carved into the mountainside at the very tip of the Baja. The entrance through the carved tunnel is awe-inspiring. Feels very desert meets the sea, surrounded by mountains, with rock outcroppings book-ending the beach. The beach is not swimmable.

Pools:
Hilton: Really large infinity pool- great for a more active swim/play. I'd say the weather is likely warmer at this location. I really prefer this pool over the WA pool.
WA: Your in-room plunge pool is something you HAVE to experience. The adults infinity pool is nice, but a tad small. After an hour or two, you'll likely want the privacy of your own room pool. Due to the tip of the baja location, can be windy here, so the temp seems a little cooler.

Food:
Hilton: variety, but nothing memorable.
WA: We enjoy the dining at WA. El Farallon should be experienced at least once. Don Manuel's is great for drinks/dessert, margs and live music. The welcome margarita is delicous, as is the afternoon chips/guac/coronitas amenity. The Clase Azul tequila gift is one of my favs.

There are some websites which can be used to help notify you of availability.