@DiskDoctor
Well Hyperion or MOS devs should make some free Amiga demo / presentation with some usable features for macs (on top of E-UAE I suppose). ... Also some printed magazines maybe, i.e. limited-time demo CD (a demo OS is a must, again).
MorphOS is a bootable livecd since forever, and it will be the same on Mac Mini (why would you need UAE?) You can install it and test freely, for limited time per session. To continue testing you just need to reboot.
If you feel that MorphOS is worth your money then you can buy license online. The license keyfile will unlock the MorphOS for unlimited use on that particular hardware.
