Not had a tw tarp. But used a 3x3, my own opinion is that they are a bit small for hammocking, ok in good weather but come winter a longer one I have found to give more protection to the ends of the hammock.... I also like to be able to take the edges to the ground, and borito the ends in in really bad weather.... Being tall and shall we say built for comfort, ive found the ridge to be to low when this is done.
Someone will be along soon to tell you different....