The White Company one is more versatile certainly, I can't think of that many occasions I'd have for the much shorter version.
That being said I would buy faux, the WC skirt doesn't look that well fitting even on the model and I find real leather skirts a lot stiffer than the faux, which tends to mean they don't fit to your body in the right places. I also think they've had their moment a bit, and aren't an ideal spring summer piece( in black especially) other than for the odd night out maybe, so couldn't justify the price over one from say...Topshop.
But if I were picking from the two, the first.