Magento 2 will need at least 6 months more to be perfect without bugs! More over, this theme is packed with many magento extensions and no developers can, in within 6 months, can update all extensions to work with magento 2.

So I think you can buy this themes to start your project, and when the theme is 100% update to magento 2, which is about 6 - 8 months later, you can find a way to upgrade it ( if only you really need it)

With open sources products, the cms version is changing frequently, and we should go with the current perfect one, not the future which seem to be better but not sure

Nice day my friend,

David, CEO