The Warsaw Marriott was generally fine, but they need some upgrades - mostly to the ridiculous bed covers. Though, if you want to be high up, the Marriott makes sense as it occupies the top 20 floors of Centrum LIM (20-39) (the M stands for Marriott). Here are my pros, cons, and photos:

Pros:

• Upgraded the night before arrival to a Business Suite / Corner Suite (views pretty good for Warsaw)
• The living room furniture and desk chair were decently comfortable
• Large windows in the bathroom make the space feel airy
• Bed mattress was oddly soft (different than the expected slab I thought it would be due to the thinness), and the pillows were plush
• Shower pressure was pretty good
• Elite breakfast is in the restaurant (not in the lounge) and was pretty good
  • Fun Big M waffles
  • Omelet was pretty good
  • Eggs Benedict on the buffet
  • Thought the croissant was pretty good
• Had to ask, but was able to get the 3 PM checkout I asked for

Neutral:

• M Club next to the restaurant exists - not much in the way of afternoon offerings - didn't try much at evening service besides the chocolate mousse covered with mango, which was odd
• Welcome gift was just a plate of fruit - no sweets

Cons:

• Bed covers horribly thin with duvets that urgently need replacement
• WiFi had horrible performance in the bedroom (fine in living room)
• Not a fan of the use of single-use toiletries
• Toilet seat seemed unstable and misaligned - I'm not that heavy, despite my macaron diet

The Sheraton is far better.

Photos: