afaict these guys are competing with Unchained and Casa on collaborative multisig. Their pricing is very uncompetitive though. Afaik both Unchained and Casa charge $250/year and then a signing fee for when that's rarely needed. 21st Capital charges relative to the amount stored in the multisig which tbh doesn't make sense to me (their obligation/work is the same regardless of how much money their customers are securing).