I stayed back in March 2012 and this was just before my Royal Ambassador upgrade. I was upgraded to a Deluxe Room as a Gold Ambassador and was on what I assume was the west wing (not on the side of the club room). I payed for club lounge access and my room was fully stocked. In my welcome letter I was made aware that all rooms with club access have a free mini bar so assume that had I originally booked a club room I would have been put on the east wing with a complimentary mini bar full of soft drinks - so seems as though I was quite lucky with the way it all worked out.
However, the club lounge in my opinion is right up there with the top IC lounges I have visited. Beers and wine are served all day - and the evening drinks and canapes are available a lot longer then most other hotels, with a wide selection of spirits.
The Deluxe rooms are also very very nice. 42 square meters from what I remember with a sofa - and overall a lot bigger and comfy then most studio suites I have had at other IC's.
This seems to be a hotel where guests opinions seems to vary a lot more then other hotels - but for me, I really strongly recommend it to anyone visiting Berlin.