Your question has been redirected her as you are comparing two things that Tite Kubo has not compared in the series nor stated which is better of the two. * If they are two Kidō techniques it is likely that the technique with the higher Kidō number is the strongest. Otherwise, it is still unknown. * It they are two techniques, one from a Bankai and another from a Shikai it is likely that the Bankai technique is the stronger. There are some very strong Shikai like Yamamoto's Shikai. * If one technique comes from an unreleased Arrancar and the other from a Resurrección then it is likely that the Resurrección technique is stronger.