I definitely think that my younger brother would be interested in that, but his attention span is too short to allow for the download speed.
I'd say that it would be good if parents got it as a surprise for their child and told the child about it after the download is completed, but if the creature has to be customized before the download, I doubt that would be a viable option.
It's also interesting that it's shipped with a USB stick. I've been wondering whether developers would start doing that at some point.