^Pokemon Reversal would be a better play for this, methinks. Even if it is flippy, chances are they'll send up an Azelf or something 'Zard can't one shot.
Most SP decks would just snipe around Rapidash anyway, and DGX would let it get KO'd. I like Infernape 4 X as a tech in Charizard; it's a fire type and continually disrupts the opponent. It also has an okay spread attack for anything you are just short on.