I’m right now at the Westin Cape Town, a few meters away. (Glad I didn’t book the AC if only because our arrival was yesterday and we could have been walked!)

The AC looks amazing from here and I can see a nice open air rooftop pool. It’s also not as isolated from the Waterfront pedestrian zone as the Westin. (It is, on the flipside, a little further from the Long Street/downtown area).

Since the suites at the Westin are underwhelming, the only factors in favour of the Westin over the AC would be the lounge. I doubt that justifies the Westin premium.

All in all, looks like another good addition to Marriott’s extensive choice in Cape Town.

I just stayed at 15 on Orange last week and am at the AC now. Overall, I’d go with the AC. 15 on Orange had a great location, if you are interested in being in more of the center of town and not necessarily near the V&A waterfront (which we didn’t love - felt like Navy Pier in Chicago to us, or somewhere equally as touristy). 15 on Orange is fairly recently renovated, although the rooms are a bit small and the open bathroom (tub in the middle of the room, literally) will not work for everyone. We were “upgraded” to a corner room with a Table Mountain view, but one side of the room directly faced some buildings belonging to Cape Town University, so we had to keep those curtains shut the majority of the time. As a party of 2 adults and one child, we found it cramped. The breakfast was decent (we live in and travel in Asia, so good by US standards but weak by Asian standards) but unless we got there early, it was a mess. Staff were overall fine. Pool is more of a showpiece than an actual swimming pool.

AC is brand new, and we were upgraded to a corner room with great views of Table Mountain, albeit over the city skyline. The room is spacious, including a nice sitting area, and the bathroom also. Our room wasn’t ready when we checked in, so we were given a standard room to shower and clean up in. That was also spacious and also had a proper sitting area. The breakfast (free for all guests) is phenomenal - definitely not the “standard” for AC hotels. Full hot buffet, as well as anything you’d like egg-wise, to order. Cheese bar, charcuterie, huge selection of breads, huge salad and veggie bar, sweet treats buffet, and a waffle and French toast station. Lots of fresh juices, a barista making coffees to order, and if you didn’t want to wait for that, a self serve coffee machine. The staff (with one exception) are enthusiastic and helpful. Parking is in the basement, though at 100 Rand (~$7 USD) per day. The downside? Location is very hard to find. We missed it 3x driving ourselves, and our Uber drivers had to pick us up at the Harbour Bridge Hotel (just around the corner, NBD). Also, you are a stone’s throw away from the V&A if that’s your thing, but due to fences, etc. it would require a walk around a few industrial-ish blocks to actually get there. Apparently there is a shuttle boat to the V&A but we didn’t take it.