UTC S series, S is for "Sucks"?

Was just looking at the UTC catalog, which describes the S series as follows:

"UTC Special Series audio units are specifically designed for the amateur and popular-priced PA service."

Does this mean limited? Based on that statement I would expect limited frequency response. They didn't publish frequency response graphs or range data, which makes me suspect they don't have great specs.

Anybody play with these? Experiences?