My son also had a huge discrepancy between K-BIT and WISC-IV, but in the opposite direction. 123 on K-BIT, 145 on WISC-IV. He is a very math-y, literal kid (not particularly verbal) and even though his K-BIT score was not a gifted-eligible score, our school recommended going forward with the WISC-IV because he maxed out on the TOMAG.