We (wife & I) had a wonderful stay at Miren's apartment in Sevilla for a week. Well located in the city centre, about 15 mins walk from the Cathedral and the famous Alcazar, with a vast number of tapas bars/restaurants close by to explore.
Miren, our host, and her husband Carlos were extremely accommodating - he patiently waited 8 hours due to our plane being delayed for bad weather, and Miren was always quick to get back to us.
The weather (in March) was perfect for us, about 25C every day. I would imagine the heat gets unbearable in the summer, but the apartment is quite cool inside and has its own shaded garden attached for sitting out .
The locals were very friendly, we just about managed to get by with our hopeless Spanish, and there is a very laid back vibe to the whole city.
Definitely recommended for a couple, we would certainly go back again.