[Dovecot] shared folders in v1.2 with one uid per user

Hello everyone.

I'm new to dovecot and I'm setting up a server for one domain only. I have not yet decided whether I will be using one uid per user or one uid for all of them.

What are the steps for correctly setting up shared folders with acls if I choose one uid per user?

What advantages or disadvantages has setting one uid for all users vs one uid per user, considering I wish to setup shared folders (including security, performance, etc) ?

Thanks in advance,

Ezequiel