We summited on June 6 and there were two people I saw with instep crampons having a much harder time "duck walking" toes out (more of a Charlie Chaplin crawl, really) up the chute. There will be plenty of steps to follow, but you'll want toe spikes to dig, and to step naturally, especially if it's icy. I've got Grivel Airtech aluminums that work wonderfully and they're light enough that you forget you're wearing them -- especially when glissading. (No, no, that was a joke. DON'T glissade with your crampons on.) Good luck.