I'd say it depends upon what your use will be.
If you are going to use it to play monophonic lead lines primarily (ala. Rick Wakeman, etc), and want that specific miniMg sound, then I'd go with the mini. Although the Arturia emulation supports polyphony (which is amazing), the miniMg as a musical instrument really was a lead instrument in its own right.
If you're more into complicated pads and evolving sound textures, then I'd choose the modular. But then again it can do leads too (unlike the real one where [in my experience] it didn't track a keyboard particularly well). But arturia's does track, so...
Or --- buy them both.