The NUC Blog reviews the Akasa Newton JC

"It seems the large aluminium case is a pretty effective heat sink. Akasa claims it will cool the NUC better than the stock fan, and my tests seem to confirm that. When I left the NUC7PJYH running Prime95 for the whole night from 2:30am until 9:30am the temperature rose slowly during the first hour until it reached 67 degrees Celsius. You can see from the graph below that the temperature never rose above 67 degrees."

Source: The NUC Blog