Arrive from China after about 1 month waiting.
Capacity only 3200mah, initial test from full batt (after 1st charge), can charge from 10% to 63% of Z1. At least can get 12 hours used (FB, tethering and chating).
I never use powercase before so this what I like/dislike:
Use the magnetic connector to charge
When connected to power, can also charge directly the phone 1st and after full, charge the powercase in dual mode.
Have kickstand for watching movie but the stand feel filmsy
Fit nicely, not loose but not cover all
Sure can protect back glasses
cheap, less than RM50 (not including shipping) - actually I get for free
Added thickness but still no issue for me, my Nokia N900 is thicker
Added extra 80g.
Cannot take pic with flash when use powercase, the flash light bounce back to lens.
Doesn't match my phone, only have white when I bought.