Comment 9 for bug 1354749

Having persistent storage is in my view preferable to showing a warning dialogue to every user.

You run into problems having used it all, which is a more of an expected error, for fewer users, and it could fail graciously at that.

Then there is the additional complexity in setting it up. Just using all extra space on the installation media by default, with no sliders required, doesn't strike me as a bad idea?