4 star hotels in UB - any up to date reviews?

I am travelling to UB independently to volunteer for an Archaeological site with the University of Pennsylvania (see http://silkroadfoundation.org/archaeology/khovd/) in June. I will be arriving In UB three days before we are required. On previous digs that I have volunteered for (Uzbekistan and Jordan) I have stayed in a 4 star hotel BEFORE going on the dig. I repeat this at the end of the dig and before departing the country. It gives me a chance to relax before and after the dig and I get to do some final shopping in a relaxed mood. When I say ‘4 star hotel’ I would like somewhere with a private room and a private bathroom, flushing toilet and somewhere to plug in a hair dryer. Yes I know it sounds ‘soft’; however I am going on a dig which will not have any of these luxuries. I have done a search on TT AND TripAdviser but I really wanted a current review. Can anybody advise which of the following fits my request:
Bayangol Hotel
Chinggis Khaan Hotel
Continental Hotel
Corporate Hotel
Kempinski Hotel Khan Palace
Kharaa Hotel
Narantuul Hotel
Ulaanbaatar Hotel
White House Hotel