No, it might actually be a different chip, some of the SPO256 chips were programmed with different allophones and even phrases, some were designed for use in speaking clocks for instance.
The 'sucks' is relative, at the time it was designed it was pretty awesome, I built a VIC-20 speech synthesizer with one in, one of my very first ever kit builds and it was amazing, must have been about 13 at the time.