Fantastic ascent. Climbed from high camp 4900m Portuelas Lomas Amorilas with Jon - en route to climbing Cerro Plata. Had sat out a period of high winds at Salta and La Hollada but after a windy start to the night winds dropped enough to make a start at 4am and from there it gradually got calmer until virtually no wind. Got a bit cold just before dawn at around 5500m but made up for by the beautiful views both sides of ridge which just seemed to get better and better. Crampons needed at around 5600m and up to final ricky scramble to the top of Pico. Actually several plausible tops - we visited all possibilities but still don't know which was the actual top! Caution needed with some unstable looking cornices and some of the rock at edge also on Mendoza side somewhat unsafe looking. Dropped down frozen scree to the col and then went on to a glorious ascent of continuation of the ridge to summit of Cerro Plata - again crampons very much required.
This is a highly recommended way to climb to the top of the Plata group - if you are confident in use of crampons and ice axe.