They were recalled as unsafe at any speed.
You should throw it away immediately!
I thought it was the 57's that had the problem, not the 58's. Oh well....my mistake.
That's an internet rumor spread by unscrupulous contractors, looking for work. If you research the CPSC logs, you will see, that although the 1957 Simmons gazorniflaptor was delisted by UL due to insufficient testing, the CPSC never issued a recall, and the actual reported incidence of fatal accidents was relatively low, approximately three fatalities were attributed to it, which was considered an acceptable risk. It you replace it with a current model, the likelihood of a Chinese counterfeit is probably greater than the risk from using a vintage model.