Well, as for inconsistency regarding the composition of a blade, I do remember that years and years ago, the Viscaria was said to have a balsa core (Megaspin had that wrong info for years on their website), probably because someone didn't know the difference between balsa and kiri.
Unfortunately I'm old enough to remember people telling others on forums that the Vis would have a balsa core and referred to the incorrect Megaspin info ("Dude, Megaspin says the Vis has a balsa core, so it must be true...

).
That being said, some of the reviews on revspin you find verbatim also on the corresponding Megaspin reviews, which means that one would have to take info from revspin with some grain of salt.
Anyway, one would just have to look at the pictures available and see that the JRE has an ayous core. There is absolutely no doubt about it, and if Gewo prints the exact composition on the box of the Hinoki Carbon Off, then we can be pretty sure that it's correct. It is also very likely that Gewo printed the composition on the boxes of the other Aruna blades. As for the
Joola Aruna Off, I just took a look at some pictures, and this one indeed has a kiri core.
For me, perhaps the most interesting difference between the Joola and the Gewo Aruna blades are these "side paint jobs" of the Gewo blades, which prevents seeing the "inside" of the blade. I believe three of them have this green paint or glue and one has a white/natural colour that even goes along the handle. Nittaku Flyatt blades have something similar.
If we were really really nitpicky or overly pedantic, these blades would actually be "illegal" or at least in some grey area. But I'm neither with the ITTF nor an umpire, so I don't care much about it. It's just a funny little observation.