I am just wondering what INON has done in order to be able to handle the roughly 50% higher Output Level.
The used to have an internal heat issue. That was eased when the Eneloops came, due to lower internal resistance.
This extra Heat must dissipate somewhere. An Aluminium Housing has a clear adavantage here.
They must have reduced the resistive losses by approx. a 1/3 in oder to compensate for the Higher Output
Ps! Engineering thinking over a Cup of Coffee!.