AA Island Map for Fuerteventura is a good, clear map with a 1:50k scale and contours at 25m spacing.
Also included are separate 'city' maps for the capital, Puerto del Rosario and a number of the resort towns, Morro Jable,Costa Calma, Tarajalejo and Gran Tarahal, Corralejo. There is also a small inset island map, useful if you want to get a ferry somewhere.
The map is a good size - enough to take cover under during a sandstorm, but quite a wrestle in a small car!
Areas which were maybe not so well covered are the dunes and the malpais (the volcanic badlands), neither of which show any contours or other real features. As the dunes shift, fair's-fair - these are not mappable. The malpais is inhospitable, and this is serious off-road territory. But if you're the off road type, don't let that stop you. It's well worth a visit, but don't try to cover too much distance - it could be a long way back with a twisted ankle. Again, in fairness, the map does distinguish between the ropy, 'pahoehoe' and the block 'aa' lava. Otherwise the relief shading was good.
The map was slightly out of date, a consequence of the pace of development - our rough road was newly smoothly metalled which speeded our progress one time.
This is a great map for hiking - it shows most of the maps for the sunflower guide and a few more besides. I'd take the map given the choice as this gives the flexibility to make your own decisions and explore the island yourself!
One thing that was found lacking was the key. Now my understanding of German is not too good, so wherever you read Baden gefarlich! it is dangerous to swim.
We used the map extensively for hiking without a hitch. The real test came when we were flagged down by a lost cyclist. We were able to locate our position in seconds!