[TYPO3] Best practice for many users and newloginbox

[Søren Schaffstein]

What would be best practice when using newloginbox extension on a site 
with something like 20,000 users in three different groups?

I'd preferthree separate sysfolders for this but this seems impossible 
since newloginbox requires the general storage page and the site uses 
TemplaVoila.

Is it really best practice to place all users in GRS and just givve them 
different groups?

Søren