Edirol R09HR Internal Mic vs. SM58 Mic Quality

I'm not an expert, but i can tell you that they are very different mics; SM58's are most commonly used in vocals, and, although i didn't hear the Edirol one, i'll bet it's more suited for location recordings, as it's a
stereo mic - i previously owned some pieces of gear with similar characteristics, and usually they are very
sensitive, and accentuate the highs a lot. So, i would bet on the Shure for vocals, and the Edirol's for more ambient type recordings (maybe acoustic guitar, or field recording,etc).

Hope this helped; greetings from Portugal