Here is Zafirah, Turkey 2011,  who uses a 3yard rectangular silk voi veil!  Zafirah also prefers  Fairy Cove's   TIE POCKET option for  securing Voi Poi Veils!

She has also  used  6mm veils, as well as 5mm weight silk veils!

The veil in this video was not provided by Fairy Cove Silks,  it might also be noted that the veil  may not  be 3yards long ... in fact, this veil in the video has a very interesting shape at the tips (which may include raw edges), but the shaping provides a unique additional visual interest!

Delanna,  appears to be using 36x72  or  36x80   simple voi veils.  They may be fairy cove, (pocket design makes me think so)

They appear  rectangular in shape. Also used is a larger veil  but not full 3yard, maybe 45x90?