What is the best product for my needs?

Good afternoon,

I will be developing a website for a new client, a law firm. They are seeking a website with a protected area for clients to log in and download files. Since this website is for a law firm, clients should only be able to view/download files that are specific to their case. An administrator from the firm would be responsible for uploading files for the client to review, and for creating client access logins and passwords.

From looking through your plugins it would seem that "Membership" is the closest for what it is I am seeking to create. Would this be the correct plugin to use? Or is there a different one on wpmudev that I should look at?

Thank you!