In the past I've heard Abs are different from other muscle groups.  You can work on your Abs everyday, but then I've also heard, Abs are like any other muscle groups.  It needs rest for recovery.  So, my question is, how often can you work on your Abs?  Can it be a daily routine or should you work on it every other day?  What's the best rest day/days between each Abs session?  Would like to achieve sculpted Abs with rock hard core.