Very true. Catwa in particular seems to stand out with very different eyes and mouths. I've just got LeLutka and some Omega heads myself and those seem a little easier.
well every mesh head designer have tweked and cerated a different mesh even if is "compatible" with dfefautl uvmap that is not erally true the only solution i found out is to wear a textuer with a reticualte and find out the post where the shape bend or crisp or land for design a sort of map. Would be great to have aobj model to paint over anyway