Roland (and Yamaha) pioneered this technology. It's used in the entire VS line's effects boards quite successfully.
The concept is simple enough:
Take a known microphone's characteristic's and, through processing, impose the DIFFERENCE between it's and another mike's known properties.
That said, if this technology is coupled with an high quality internal preamp (for which Roland is NOT normally known ) you could have a killer product as the front end of any recording setup!