We stayed in a 2-bedroom condo with the Mt Yotei view, and were happy with the staff, facilities etc.
The best thing about Ki Niseko is its top notch location and the ski valet service. Once you get your ski gears (if you hire them) fitted at YamaSport (170m from the hotel), they'll transport them to the hotel for you. The ski valet service takes care of getting you the gears when you go out to ski, and putting them away to dry on your way in. The hotel is literally 100m from the Holiday Pair Lift (you need to walk slightly uphill), and another 100m away is the Grand Hirafu Gondola. Going back to the hotel is super easy - you literally ski all the way back to the entrance of the ski valet.
The private/family onsen is a wonderful touch, for those who aren't brave enough to mingle with strangers, naked.

This was our second visit to Ki Niseko in January to ski. This time we splashed out and took a penthouse to share with family and friends. It was worth it!! 4 generous bedrooms and one small bunkroom, all with ensuites; large, well appointed living spaces with plenty of space and a well designed kitchen. This was all beyond our (already high) expectations. But what makes Ki Niseko feel like home is the staff. The effort to get to know you personally and pay attention is warmly appreciated (thank you for my bringing me my slippers every day in the ski locker, Elliot), as is the high quality, consistent and cheerful and patient attention before, during and after the trip (thank you, Ciara, our outstanding and dedicated concierge). I can't recommend the team and the place highly enough. Oh, don't forget the onsen - sitting in a hot bath with the snow drifting through the pergola was a treat we looked forward to every evening.

Was our 3rd season at Ki, everything was expected. Here’s a quick summary -
1. Check in - very smoothly as the staff was very helpful.
2. An Dining - Poor attitude, when they were full at lunch. They cannot call us in the room. The manager also turned me down when I was perhaps 3 minutes late and he didn’t even offer me alternative eg sandwiches or something that didn’t require the kitchen to make. He then gave me his name card to tell me to complain him. He had been there for years. He had this “I don’t care if you don’t’ ever come back attitude.’ He knows they only have 1 restaurant onsite and they are always full! We definitely will not ever go back to this restaurant and gave us a bad impression about the hotel altogether, as the hotel told us they are a separate entity so they cannot control how they treat their guests.
2. Room - started to notice some wear and tear in the room. The apartment was very small. Luggage had to put next to the door. Another put next to window sill.
3. Ski in ski out - this is the best as its only 3 minutes to ski school and lessons and a few more minutes to gondola. We always ski in the morning even when we check out. We can go back to dry our gear and take a quick break at lunch during the day.
4. Spa - very small but very nice and friendly staff. I got a few very nice massages which I slept through.
5. Onsen - private but need to book and only allow once a day per room and limit to 30 minutes. I still went very night .