Those worked great for me when I was in Japan. Google Maps was also great for getting around, it would have been really hard to navigate without it.

The hardest part was navigating services. It was really hard to figure out how to get IC cards and cell service, and getting online tickets was a nightmare dealing with horribly buggy websites. I normally like to plan things on the fly when I travel, but for Japan I really recommend doing research ahead of time and getting tickets for things you want in advance.