hi, was wondering if anyone here used the pocket wifi before when you guys are in Japan?
I'm going there with a friend and we were thinking of renting this pocket wifi from

http://globaladvancedcomm.com/pocketwifi.html
(just in case we hilang, at least still can google map LOL)
10 days rental = 6600 yen with tax (collection from airport post office)

Another alternative is the visitor sim from b-mobile.
1GB for 14 days = approx 4200 yen with tax (collection from airport post office)

A bit dilemma now.
And when they say UNLIMITED DATA, meaning there's no quota on the wifi rite? (coz i'm no gadget gizmo, so a bit blurcase here)

Any advice on this as to which is better?
main usage is watsapp, google map (MOSTLY) and routes to use (just in case sesat jalan)