We stayed at Manuel's beautiful apartment for nearly two weeks. We were looking for a base from which to go on some hiking excursions and also to do a bit of work on the computer, and the apartment was perfect for that.
For hiking, the apartment is wonderfully located. All three major hiking areas are accessible within about an hour's drive: Teide, the Anaga mountains to the East, and the Masca / Teno area to the West. When we told Manuel of our hiking ambitions, he gave us some terrific advice.
The apartment itself is a gem. We loved having a proper desk from which to work -- we hadn't noticed it when we booked. You could not improve on the view from the balcony, and it was a delight to take meals there. Meals were easy to prepare thanks to the fully equipped kitchen. We didn't use the extensive CD and DVD collection, but enjoyed browsing some of the interesting books in Manuel's library.
For groceries, the farmers' market in La Matanza is terrific. There are options all around, but we had things to do in Puerto de la Cruz and often got our supplies there (Lidl, Hiperdino, Mercadona and about a dozen health food shops!)
If you're looking for a comfortable base in Tenerife, look no further.