I have done XMN transfer last October. The lounge and the hotel. Not the sightseeing tour.
The business class lounge is small and limited in food. There were 2 hot Chinese dishes. very very few cold options. The "sandwiches" are in the little fridge. when you see them you know why I put them in quotation marks.
During the day it is very quiet but a door to the bus gate waiting area is always open. If I am not wrong this area is also the waiting lounge for economy class passengers. So they literally sit at a better bus gate. Seating inside the business class lounge is comfy.
Shower facility is available and clean. There are few sofa's were you can catch some sleep. Lounge fills up for the evening flights. Beer is lukewarm even tough stored in a fridge.
The lounge is on the lower level so you are on tarmac level and you can sit directly at the road looking at some of the gates. But it gets boring after a few minutes as you can't see anything left or right.
The hotel is the much better option: I flew business class and the hotel is owned by Xiamen Airlines: Xiamen Airlines Lakeside Hotel. The taxi costs just above 40 RMB each way.
The hotel is located next to a lake. The room was very large with view over the lake. On the elevator i saw some floors marked with no smoking signs. It seems that the hotel is not fully non-smoking. I had a room on a floor that was not showing a non smoking sign. Next time I will ask for a room on a floor that seems to non-smoking.
Hotel seems to be upper class and I even met a captain on his layover there.
There is a left storage facility just after customs at the airport.
Make you need the blue arrival card for the free 72 hours transit visa. When I arrived on my inbound flight with KLM they gave the yellow one which is for normal visa holders. In case you have the wrong arrival card you can pick up the blue one just before the immigration counter.
BTW: both legs have to be on Xiamen Air and not a codeshare (KLM for example) to avail of the options. This will be checked at the transfer counter (which is after immigration and customs).


Hotel room for business class transfer passengers


Immigration card for free transit visa.


View from hotel room.


Hotel voucher