Yes, mulberries are worth it. They would be a very popular fruit if they could handle the rigors of transport.
If you can track on down in the UK I'd feverishly recommend Pawpaw (Asimina triloba), a custardy fruit with such tropical flavor you'd be shocked it is native to North America.
If you can track on down in the UK I'd feverishly recommend Pawpaw (Asimina triloba), a custardy fruit with such tropical flavor you'd be shocked it is native to North America.