i highly recommend this phone instead of grand duos
battery standby is 2 days
best record of mine is 2 days 12 hours with everything is ON except bluetooth
heavy usage (when i use waze for whole day to drive in Shah Alam) is drop from 100% to 40% within a day
i am more than satisfied for the battery consumption

the weakness is, camera is not good as other high end phone but still comparable to grand duos
for casual usage, i think its should be OK
the most disturbing is the internal memory.
with 4gb, and free space of 1gb, u will have problem with apps installed because the cache is stored in the phone memory
even if u move to SD card, there is still few MB will left in the phone.
after tons of app installed, memory will be full.