Our stay at Alfonso's apartment was fantastic. The amenities were exactly as we expected, and we had no issues whatsoever.
The apartment is quiet, yet situated very conveniently. Everything you need is very close by (shopping, cafe's, tapas bars, etc). It's an easy (and wonderful) walk to the more touristy and central parts of Seville.
We really had a great time, and Alfonso provided many great recommendations. A great host, with a great apartment.