I liked the Park Hyatt Busan a lot, but I also got really lucky with my upgrade. Here are my impressions and photos:

Pros:

• Upgraded from 1 King Bed to Marina Corner Ocean Suite and placed on the highest guest floor (29) - this upgrade showed up the morning of arrival
• Stunning views at all hours
• Bed is comfortable - plush mattress, soft pillows, covers of okay plushness (fine for climate)
• Shower pressure was strong (I used the wand)
• Staff was friendly
• Offered late checkout - no issue with requested 3 PM
• Breakfast was good - I enjoyed most of what I tried and my iced latte was good (PH Seoul is better, but I would expect that)
• Nice welcome gift of cookies and beauty masks

Neutral:

• There is some wear but it doesn’t really bother me and isn’t that bad

Cons:

• Since I was on 29, I could hear some movement on the lobby floor above
• I could not figure out how to use the rainfall shower head - unclear if I’m dumb or if knob was broken

I would come back here.

Photos (please expand the Spoiler tag):