I have been using Naviwax all this time, and it is the best wax I have used thus far. Easy to apply, lasts long, and brilliant shine. Not expensive too.
I went to Autobacs several times but noticed they no longer sell Naviwax.
But the last time I went there and I asked one of the Japanese supervisors, and in his broken English, I think he was telling me that Naviwax in Japan "no more" but now there is a replacement product by the same company Taiho:
Bought one can (200 g) for RM58+ (Japan is selling it for about RM50). Tried it on Sunday, and absolutely brilliant shine. Neighbours joked I "re-bought" a new car.
However, the new product smells less pleasant -- more like petrol. I can't read Japanese, so I don't know exactly how it should be applied. The "old" naviwax is applied by either misting the surface with water or wetting the sponge/applicator a little with water then applying the wax.
I tried the same technique with this "new" product but the wax didn't seem to stay on. At the end, I applied it dry, then wiped off almost immediately, leaving a slick, oily feel.