It is a new paradigm, totally private money with no scalability issues backed by bitcoin.
And with federations we will avoid the custody problem.
Discussion
Absolutely. Even without the federations it's already a huge step.
You can have mints of various sizes and action radius managed by Uncle Jims. And then for you, as a client, it's just yet-another-custodian where you can drop part of your hot funds. No sense in storing your life savings in a cashu mint ran by some random internet guy, just like with Wallet of Satoshi. But beer money? Why not.
Indeed, you can create your own mint in just 5 minutes and issue your own tokens. You can pass them on to a third party who simply by adding your tokens in their cashu wallet will be asked to add your mint and redeem them.
When I think about how big this is it makes my hair stand on end.