Why the Grimsby-class sloops earned a good reputation

Were the Grimsby-class sloops good ships, and where did they perform convoy duty?

Yes. They are described as effective small sloops whose convoy work was concentrated on the Arctic routes.

The initial answer calls the Grimsby-class ships very good little sloops that performed a great deal of useful work. A later follow-up places their convoy service primarily on the Arctic route, though they also appeared on Atlantic duties. That setting explains the emphasis on hard service in cold and dangerous waters. Opening both moments gives a compact assessment of the class and the operations behind its reputation.