Kevin Lalli wrote an answer about Salomon Guardian 16 Alpine Touring Binding on October 19, 2013
As a general rule, big symmetric skis do well with a mount closer to the center of the ski. Not sure about the 7's in particular. The idea with a center mount is to put your boot in the sweet spot of the relatively short running area, and also reduce the swing weight of the ski. That helps a lot for pivoty turns in the trees and such.