I had a 3-night paid stay 18-21 December and really enjoyed it. The location is just so good, and the club lounge is perfectly satisfactory for my needs. (And it was very nice to have the lounge staff remember me and even my preferences -- eggs scrambled with cheese -- from my last stay.) I used a TSU to upgrade to one of the (very small) suites and then paid the delta (HKD 300/night) for a harbour view suite. In retrospect I would have saved the money because the view from the suite is really quite obscured and the view from the other end (non-view suite) is still pretty good. Only from the bathtub of the harbour view suite can you really see HK harbour.

Was meeting others who were staying down the road (Royal Garden) and they came over for 2-for-1 happy hour at the 3rd floor Chin Chin bar -- had a good time.

Seems like the K11 mall keeps getting improvements / new shops and it was indeed fun to walk around at Christmas time. The direct indoor access to both TST and East TST MTR stations (2 floors down in the mall) is really hard to beat ^