MiniMig is brand new so is less likely to fail than old equipment.
MiniMig is smaller than an A500 so can be more easily fitted in to your house.
MiniMig uses disk images on SD card, so no need for stacks of floppies.
MiniMig can be built in to any case you want.
MiniMig supports VGA monitors directly without the need for expensive scandoublers.
Anything else? ;-)
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moto