Stayed here for 1 night recently.

Attempted to check-in around 12:30pm, but was told outright that check-in wasn't until 3pm. I mentioned I was "Gold" at least three times, but that didn't seem to sway things. They did offer to store by bags, so I moved away from the check-in counter to get a few things from my bags first. After about 30 seconds the person that I'd been talking to came back up to me and stated he'd just realized I had said I was Gold, and that he'd be happy to check if they had a room available, which they did!

As was mentioned above, the elevators use an automated system where you just swipe your card and it tells you which lift to use (based on your room number), but I can't help but feel the way this works pretty much sums up the hotel - a good idea, but poorly implemented. Above the card reader is a number pad, which is common of elevators in Seoul - you enter your floor, and it tells you which elevator to use. The problem is, hitting any number gives a message that the floor you're after is "a non-stop floor". Pretty much everyone seems to fail to see the card reader, and just tried typing numbers, and gets confused. Some swipe their cards, then try and hit the floor number, which again gives an error. There is *zero* signage or any other indication of how it's supposed to work, and it certainly wasn't mentioned at check-in. On the other floors there's no card reader, just the number pad. But there's also no indication of how to get to the ground floor! There's a "B", "C" and "0" button to help confuse things, but you actually need to hit "1" (which makes sense - but some signage still wouldn't hurt!)

The room itself was small but fine. I was on the road side, so didn't have the train noise issues mentioned above.

Breakfast is not included. Or perhaps it is... The restaurant has apparently renamed to "Million Spoons", and there's a sign in the room saying that breakfast is 25% off for hotel guests (normally 19,800W, now 14,900W). There's a sign in the elevator that states "Free Breakfast" (in English) - https://imgur.com/NVGU7qt however according to Google Translate the text under it states that it's once per stay, and not relevant for corporate rates (which I was on). Breakfast can't be charged to your room - you need either a coupon from reception, or to pay "cash" (Or possibly card, but they specifically said "cash"). After having a look around what was available which wasn't overly impressive I ended up just going to a cafe across the road.

As far as the comments above around "brand standard", Marriotts website does state that breakfast isn't included in AsiaPac Fairfields, although it's certainly not called out as clearly as I would have liked.