zoho.loginuserid VS zoho.loginuser?

I understand that zoho.loginuserid is the Email address of the logged in user and is null for a public user.

I also understand that zoho.loginuser is the User ID of the current user and is "Public" for a public user.

I'm concerned that since email addresses can change over time, my views will break if I use zoho.loginuserid.

So, is it best practice to filter views with criteria like Added_User==zoho.loginuserid, or Added_User==zoho.loginuser ?

Thanks,

Jeff