There are different sources for these concerts, i didn't compared with all of them and the files doesn't mention the source.
They sound excellent but, again, this is a bonus, the item is the mini guitar replica. The content of the bonus is not what matters really.
That's your opinion, others take a different view. Frankly I see a lot more questions from people about the music than the model, suggesting the music matters more to a lot of people.
And my opinion is that they are wrong. A product that includes other items, it's still a main product with other items that are not the main product but part of the package.
If part of the package would be better or more interesting than the main product, it won't be part of the package but the main product itself.
I see it very logical, but that's me.
Of course I understand everyone dreams about unreleased stuff being released in any way but, again, if that happens, logical says it would be the main product, not part of the package of a main product.
If you are not interested in the guitar, don't buy it for the usb. That's MY opinion.