We were at the Hesperia Del Mar in October 2011. The hotel is nice and well located near the sea. There are plenty of Restaurant on the main street in front (Passeig Garcia Farria) as well as just behind the hotel on street like passeig Taulat and surronding streets.
The hotel is considered as a 4-star hotel but it is really a 3-star. The entrance is a bit strange as you have to go down to a lower level than the street to get in. There is though a small elevator to get there if you have heavy suitcases or for handicapped people.
The room we had 111 was rather small but the bathroom was spacious, and had bath, shower and bidet (see pictures). The hotel is quiet and that room gave on a park behind the hotel. The staff is friendly and helpful. We have asked about restaurant and were always well advised. For anyone interested, there is a Hotel and restauration School just on the street behind called Escola Hotelera de Barceloa (on passeig Taulat) and they serve fabulous meals from Monday to Friday. We went to their upscale restaurant and a 5-course meal for supper costed 21 euros.

The nearest subway stations (there are 2 at equal distances) are Poble Nou and Selva de Mar, at around 10 minutes walk. The bus # 41 passes in front on Passeig Garcia Farria and will get you to Plaza Catalunya which is the center of Barcelona, where you can walk to Las Ramblas and the trip takes about 20 minutes. This bus will also go near the Arc de Triumf and the Barcelona Zoo.
All in all it is a good hotel but I would say it is a bit pricy for the quality you get.

Extremely small room with inches of space around double bed, wall and desk, very small closet
The first room we were given the electronic key used for turning on the lights, did not work. The second room was a smoking room and the third room we pretty well had no choice since apparently there were no rooms available to upgrade.
There was no room to open and store our luggage - we had to place our suitcases in the small
hallway leading to the door and step over them to get in and out of the room.
The reception was very unfriendly and on top of all, there was no one offering help with the suitcases since you had to climb stairs down to the reception and at departure up two sets of stairs.

My trip was on business and my company booked me into the Hesperia Del Mar it would not have been a choice for a personal trip but it was close enough to the CCIB (conference centre) for a welcome brisk 15 minute walk at the start and end of the day. My room was clean and comfortable and the bed was OK if a little firm for my taste. The staff were also very welcoming and friendly. From an entertainment perspective the hotel falls a little short, English television channels were few, two, and only covered News. The location of the hotel is a good distance from Las Ramblas and so would have required taxi journeys to see any sights. In sum if you are going to the Barcelona CCIB I would recommend the Hesperia but if you are going as a tourist find something closer to the action.

We went there to avoid cold winter in Sweden. And it was a great experience to stay in a good and quiet hotel for a week. And I guess the winter price we got is half of the original price. A good value!
The hotel is designed good so that every room has a side view of the ocean.