Describing a contract as "bulletproof" and drafted by "top attorneys" is likely considered puffery [1] under the law, and should be fine in my opinion.
Puffery has no place in the practice of law or -in this case- legal document drafting.
The courts take a dim view of this sort of thing where people might detrimentally rely on this explicit promise that Bonsai's contracts are "Bulletproof".