In reply to genericflipper:
I was there last January and done the Pico Arriero to Pico Ruivo traverse there and back in trainers.There are a few tunnels on the route for which a head torch could be useful but you would probably get away with a mobile phone light as they are fairly flat inside.The return route on the eastern side was blocked off with a sign saying a landslide had taken the path away but I went along it anyway and there wasn`t a problem.
Pretty impressive scenery !
Pico Grande is a good day out with just a bit of easy scrambling to the summit.