What can I say: the pictures do say it all... We did the "W" a couple of weeks before the fire brook out (which is so sad, especially when humans are to blame for this fire). The "W" was more challenging then we thought (the last 45min up to the torres are steep as well as the french valley) but it is great, especially due to the 5 days of sunshine :).
Some small tips:
Hiking Poles - We did not have them with us, but when the weather turns bad I can imagine poles can be helpful (some parts are really rough and steep).
Water - Just bring 1 bottle and get your free refills from the streams :)
Pack light - No additional information required I guess.
Towels - Despite that we booked the refugio's (incl bed, food, sleeping back and towels), some refugio's did not have any towels available anymore. Not to worry as we brought are own, so bring some (just in case).
Headlight - If you wanna go up the torres in the morning, a head light is a must.
Sunblock - Yes it sounds almost too good to be true but we had everyday good weather and sunblock is a must not to burn alive.
Map - All paths are very well marked and you will get a map upon entry.
French valley - Regarding the French valley, go as high to the first view point and not all the way to Campamento Britanico. It is a real demanding part and everybody we saw said that the view does not change fundamentally after the view point (30 min south of Britanico).
Last but not least: respect the park rules so that everybody can enjoy this amazing park.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.