Last year I stayed at Hotel Claris in Barcelona.
http://www.hotelclaris.com
This property is so well located that you can walk absolutely everywhere. I loved the rooftop pool with La Terazza restaurant. The hotel is run by ex Maybourne executive therefore the service level is top. I loved the champagne they offered us upon arrival prior to checking in. We were also upgraded to a Duplex suite with one of the most amazing bathroom amenities I have ever seen. The hotel owners are very much into ancient art, this reflects in every aspect of the hotel.
I would recommend this hotel to absolutely everyone. Lastly, during our stay we visited MO (5min walking distance from Claris). During our visit - three outlets in total - they completely messed up our food/drink orders. The entire experience felt like 'a convey belt'.