I can report some success. Kit: A2Z rear single speed kit with 16T, 4-Jeri sprung tensioner. Original 38T front chain-ring and 9sp chain.
I originally set it up for 18T but found the chain jumping under moderate pressure when I fitted the 16T, so had to shorten the chain to suit. Unfortunate, as I wanted to swap between the two gears freely.
First commute on it this morning, something has a slight vibration and noise which I suspect is the bearingless jockey wheel on the tensioner. But pretty happy with how easy it was.