The best user experience is installing the MIM client add-ins and extensions. As soon as we enable the MPRs, and a user who is a member of the Password Reset Users set logs onto their computer (which also has the MIM add-ins and extensions installed), a browser window connecting to the Password Registration portal will open.
If you choose not to install the client add-ins, users can access the Password Registration portal manually. The experience is similar, but using the add-ins and extensions will probably increase the number of users actually taking time to register, as they will be automatically prompted to do so.
If we used the FQDN for the Password Registration portal URL, we should make sure that the URL is in the local intranet zone of the client so that IE can use Integrated Authentication. To get a good experience with MIM, I recommend adding *.thefinancialcompany.net
to the local intranet zone. Like some of the other windows, the password registration window...