Both of my proshop guys have them in their arsenal. Both are midwest regional players.  The lefty just went 83rd at the Nationals in Milwaukee which isn't shabby out of 600 plus bowlers.  They both claim the Hard Core is a great control ball, they say it does what you ask it too. No over and under, good control of the break point. When I asked them to give me a comparison to a ball I am familiar with they said it rolls like the original Inferno except it handles oil much better. Hope this helps.  You could contact Paul Nicholas at Circle, he is a great guy to interact with and is honest with his opinions.