Unfortunately the 7070 was incompatible with the models (such as the 705) it was intended to replace. A simulator was needed to run programs written for older computers though the waste of resource and incompatibilities meant the 7070 was a bit of a flop. The later 7080 was said to be fully compatible. Also coming later were the faster 7072 and 7074 in the early 1960s. They were replaced by the highly successful IBM 360 within a few years.
|IBM 7074 (Public domain image)|