Cases for E-ATX

To geeks and techies of call kinds: I've got a question about motherboard sizes.

Without going into the details of the planned build, the motherboards I'm choosing between are:  

The ASUS P8Z77-WS: (12.0" x 9.6")  http://www.newegg.com/Product/Product.aspx?Item=N82E16813131822  

And the Gigabyte G1 Sniper 3 E-ATX (12" x 10.39") http://www.newegg.com/Product/Product.aspx?Item=N82E16813128552  

The problem I'm having is that I would much prefer to use a mid-size tower rather than a full size tower. (because of both space and cost) I haven't dealt much with E-ATX boards, so I'm wondering if the less than inch difference between these two boards is why the larger board requires a larger case, (in which case It may be possible to find a mid-sized tower with enough room) or if there are also other differences such as mounting differences between the board form factors. The ASUS board is already a bit bigger than the average ATX board anyway, but some of the mid-size cases seem to have enough room between the motherboard and drivebays to still handle that extra inch. E.G. http://www.newegg.com/Product/Product.aspx?Item=N82E16811112354 or http://www.newegg.com/Product/Product.aspx?Item=N82E16811163181

Any help would be much appreciated!