You cannot trust them. They all hear the same Whisper.
Threshers are upstanding people, honest and forthright, friendly and cooperative. They speak flawless Common and invite anyone into their inns and markets and even farmlands.
They are the reason the high elves have fled to Umardothiel.
They uphold many of the virtues of civilization--the good of the many before the good of the few, progress and growth, loyalty to one's family, safety and justice for the people, a healthy economy through a free market.
They alone waged territory war against the Ophidians of Mashka Sipa. See now how they avoid any Ophidian lands?
Humans are particularly brotherly towards the threshers, for they were one race half a millennium hence. It is not always easy to please humans, so fractured with their diversity and so constrained by their cultures, but the threshers are excellent diplomats and estwhile allies.
They buy alliances without need for conquering, for what fool would challenge an armored, four-armed drone with a city of soldiers at his back?
However, despite their spotless attitude and the enviable prosperity of their city-states, threshers continue to suffer many malignments from other races. Their faces are not pretty enough, and their race's origin is not divine enough, to earn credence from longer-standing races.
They wear a smile like a mask, but it is no more genuine than their forsaken humanity.
In truth, doubtlessly other humanoids feel inferior to thresher organization, efficiency, and widespread contentment in their lives, no matter their title or station. For threshers, a good life is not solely the domain of the richest or most violent.
Don't go to the White Cities. If you look too closely, you'll be seen--and gods help you if the threshers take you.
