Cuban converted trawlers and the frigate label

Is Cuba's converted-trawler class the worst frigate currently in service?

It is treated as an armed converted trawler, with its classification as a frigate disputed.

The Cuban vessels are described as converted armed trawlers. Some other ships carrying the frigate label are considered worse. Their place in a frigate ranking is secondary to the dispute over whether the trawlers should count as frigates at all.