I absolutely love that bag!! Why would she not make that design available on her own site? I did see something similar on piperlime, but the strap does not look the same (I prefer the way it is on the yellow):
www3.assets-gap.com/webcontent/0006/772/070/cn6772070.jpg
I wonder if she signed a non-compete clause or something with & other stories? I'm surprised she hasn't used magnets in any of her own bags yet. I think it's genius.