Can someone tell me the difference between the ELTD PU Leather Cover Case III and the ELTD Slim-Book PU Leather Cover Case please? Both shown here:

http://www.amazon.co.uk/gp/product/B00G5Z90ZA

Is one lighter than the other? I think the ELTD and ISVO cases are in fact the same case.

I'm tempted to get the VOIA Single Stage Case due to being much lighter (http://www.ebay.co.uk/itm/171257626750) but that's twice the price.

Thanks