Santiago's apartment is a very nice apartment. It is nicely decorated, LARGE and ROOMY, with high ceilings. 2 bedrooms and 2 full bathrooms make this a very easy place to stay. The location is perfect, easy walks to anywhere in Sevilla you want to go. 15 minutes to the train or bus stations; 15 minutes to the Cathedral or Alcazar. And as others have said, do NOT worry about noise because the apartment is above the bar. Santiago's place is VERY QUIET! Especially the bedrooms which are on the back side of the apartment. You won't be bothered by noise. :)
However, we did have 2 problems. First, it appears the wifi is on a "metered" system, and once this data limit is reached, the speeds get SO SLOW that the wifi is not usable. Our last two days were without wifi, which unfortunately, we needed for our ongoing travel plans. This is a major drawback. Secondly, although there is a full kitchen, it is not really outfitted well if you're going to do any "real" cooking. No sharp knives, no cutting board, etc. We ended up going out and purchasing several kitchen items that we needed in order to cook. This may not be important to some folks, but we always look for a real, working kitchen as we do a lot of our own cooking. YMMV.
Other than that, Santiago is a great guy and very willing to help you, although he only speaks Spanish. We didn't find this to be a problem, because with a bit of gesturing, a bit of Google-Translate, and some goodwill, we both were able to get our messages across.