Originally Posted by MRT2

You don't get much for $400 to $500. What you will find in mountain bikes at that price range are heavy, slow, and not the greatest quality. If that is your budget, go with a new hybrid like the ubiquitous Trek FX 7.x, Jamis Coda Sport, Kona Dew, Giant Escape, or Specialized Sirrus Sport. Any of those hybrids would make a much better commuter than any $500 new mountain bike.