That's understandable. The question is different - how to get the most optimal one out of this multitude of ways. In my opinion, the key to the solution lies in overcoming the Coulomb barrier by holding the gas on the surface.
In a plasma based LENR system which is the best type of LENR system, the coulomb barrier does not apply.
The LENR reaction seems to have many faces. It is amazing and wonderful that the LENR reaction can exist in a plasma. It is my guess that this ability to function in a plasma is due to the Bose condensation that these plasma systems seem to create. We know that a number of such systems produce transmutation, SAFIRE, Chukanov, Rossi, and the Egely dust system. It is my belief that the plasma based LENR system is the only type of LENR reaction that will produce useful energy going forward because of the destructive nature of transmutation on solid matter.
It is also likely that the SunCell is also a plasma based LENR system.