I wouldn’t do that, except if it’s a eBook, or DVD on marketing, or advertising I.e... Here’s why.
SFI’s got many incentives available to pass on to your down line. Gift cards, PSA’s, etc. Rather use those.
I don’t see the point in rewarding someone with something that’s not SFI related. After all... You would want to reward someone with something that can help him grow in his SFI business, right?