The roms work very well, the only thing you have to do is copy it along with the keyfile on the directory of winuae or the emulator of your choice.
If you buyed previous AF packages, you can upgrade for free, as i done this morning with my 2005 premium upgrading it to 2006 premium and yes, including the 3.1 disks.
Note that i don't like the site down politic of cloanto, but the only way to get the roms legally are taking it from your amiga or buying Amiga forever.
If you had already an Amiga and cannot take the rom out, i don't see anything wrong in downloading it.
Just my two cents.