Anyone out there have any experience with the assembly fixture that is sold by Contract pros out of South Dakota for putting boxes together?

Heres the link to the item:

Was wondering what you thought if you've used or purchased one.

Does it work?

Worth your investment?

Does it work without major adjustments where one can assemble boxes other than those made by contract pros?

Any other comments on this item or their service !!!!!!!

Thanks, Honey-4-All