I also tested the canalizer and it’s clear from the videos that it works in a similar way to the fin fences, effectively limiting the spanwise flow on the vertical tail.
You can see how well it works in horizontal KE; it’s interesting that it also helps with the airflow around the fuselage (less air moving from high pressure side to the low pressure side.



In KE loops it has its limitations though, probably because is too far from the vertical tail to effectively help in all situations. Compared to the modified fin fences, there’s more spanwise flow.



In KE loop exits, when high rudder deflections are required, both have their problems, but there’s a noticeable improvement in rudder response compared to the normal configuration.



Anyway, not all models are the same so results may be different, but in my opinion if you’re looking for a way to increase the rudder authority, the second version of the fin fences worths trying. It’s very simple to manufacture them, they weight almost nothing and they don’t have any negative impact on the flight performance. I will definitely keep them on my model.