I stayed at this hotel from Jan 30 to Feb 4, 2007 and loved it. It was my first time in Buenos Aires and the front desk staff made me feel welcome from the time I stepped out of the cab. My Spanish is elementary and they had no problems helping me in English. The elevator is an antique but it's good if you don't have much luggage.
The front desk staff, especially Javier (the evening front desk clerk), were amazing. He helped me pick Tango shows, day trips outside B.A. and club recommendations. The breakfast was the usual bacon and eggs type deal but if you walk a few blocks there are excellent cafes with medialunas which are like little croissants.
The room was spacious and the bathroom was clean and even had a jacuzzi.
The hotel is located a short walk (about 5 American blocks) from the Recoleta cemetery so you can see that on your first day there. There are plenty of Banelco or BNP ATM's that dispense pesos. Taxicabs are cheap but some cab drivers refuse to accept peso notes that start with a G or an H (the cabbie told me that these were "expired" notes with no value but if you go to a bank you can change them for newer notes).
All in all this was a great experience and don't forget to get good restaurant and parilla recommendations from the front desk.

I just got back from BA and greatly enjoyed my stay at the hotel. The hotel was in good condition, although the elevator is a little bumpy upon landing on the apropriate floor. The staff is excellent and provided recommendations for both seeing the town and good restaurants. Lets not forget that it is a steal of a price with the weak Argentina peso.

I have noticed a bit of a backlash against Kemplinski Hotels in Buenos Aires, but I stopped here for 1 night after a flight in from the UK in January, as I had another flight to take me down to Patagonia the next day & I liked this hotel so much I rebooked an extra 3 nights here near the end of my trip, through expedia for about U$80 a night.
I really liked the location of this hotel, it always felt safe & was an easy walk to either the Microcentre or Recoleta. There was also a subway station about 10 minutes walk away.
The rooms were really nice & clean, with a helpful staff & I always felt safe here. The breakfast was excellent. The only complaint I had was the dodgy, small elevator, but it kind of added to the charm. At the price I paid, I would stay here again.

Went to Antarctica this month and had a layover in Buenos Aires (BA). Wasn't too interested in BA (big, hot Latin American city), and was wary of where I'd be staying. But the Kempinski Hotel Park Chateau is in a very nice part of BA. The staff was friendly and helpful. The hotel location is in a modern, clean, somewhat European and somewhat ritzy part of BA that was great for strolling and people watching (there's also a lot of traffic in BA -- some of the narrower streets offer a little too much vehicle exhaust). The hotel was very clean and quiet, with modern and very functional facilities. The breakfast that came with the room was adequate. Would definitely stay there again. Maybe I'll go back and look into the world of tango. Perhaps on my next trip to Antarctica, which was well worth the trip!