Foot stance compared to mast/front wing

[plummet]

I notice a wide variety of foot position in relation to the mast and more importantly front wing.
I assume its a combination of personal preference and foil design that determines the foot position and ultimately where the center of balance is.

What are the advantages/disadvantages of having foil designs with your feet further forward compared to further back? Does it matter at all?

[dylan*]

In all of those pictures (except maybe the last one) it looks to me like center of mass is roughly on top of the front wing. This is where someone told me to put my weight when I was learning and it seems about right.