Apotek Hotel is conveniently located in the downtown area of Reykjavik. The entire staff is completely amazing; they provided helpful information regarding the sites, transportation and parking (there isn't any parking on-site).
I chose the single room and was taken a bit off-guard by the small size of the room, given that the price was somewhat high. Though the shower was more than adequate (spectacular, really), the bed was situated directly next to the window and the drapes. The issue is that when sleeping, if you are a person who does not lay still while sleeping, you encounter the very real possibility of rolling against the drapes. During the spring and summer months, when the sun chooses to not actually go down at all, that is certainly problematic. I woke myself up a few times because the drapes happened to part slightly and the oh-so-bright sunlight (even at 0200) was not so kind to my sleeping self.
I did dine at the hotel restaurant for dinner one night, and the staff there was also quite spectacular.
Overall, this hotel is fantastic, with the only real issue being the proximity of the bed to the drapes.