For anyone in Australia who needs some replacement 360 cases, ShoppingSquare have some.
http://www.shoppingsquare.com.au/p_13962_XB3__Game_Case__Green$0.82 each, and you can only buy a maximum of 10 in each order. You can find out postage from the shopping cart screen.
I bought 10 last week, as they had a free shipping deal on them. They arrived today.
I'd say the pros and cons are mostly the same as for the cases in the first post on this page, except the first con - these feel and look more like the real ones.
Without measuring, I think the spine might also be 1 or 2 mm thinner.
Definitely worth getting if you have cracked cases or sticker residue all over them.