Minimig is essentially a hobbyist toy for those who want to play with an A500 + some nifty features. Low production volume (and limited demand compared to something like an Eee PC) means it can't compare from a financial standpoint. (I like the MiniMig, but since I have a few OCS Amigas to play with, and nothing really to contribute from a development standpoint I probably won't own one.)
Heck -- I just helped my girlfriend put together a super-fast (for her needs) dual core, with nice heatsinks, CM case, decent RAM, quiet fans, Seasonic PSU, etc, etc, for less money than I've seen some A1200 turbocards go for lately.