The beauty of the sunflower guides is that they don't try to cover too large an area. A guide for the best bits of Hierro and La Palma means there is a huge amount of detail. If you love OS maps at home then you'll find the Sunflower maps an excellent substitue abroad. Add to that the photos and route descriptions and you have a superb resource when you're out and about. Finally, the background information on buses, places to eat, weather etc. is excellent too. We used it to self-guide some stunning walks and drives around El Hierro. Whenever we know we're going walking then I look for the blue bible!