Original Samsung battery sold by "Sorze"

As a replacement for my Samsung Galaxy W bought after this almost daily crashes produced after 20 months use or the battery level dropped to below 10% within a few minutes, but rise after some time the Out Turns one without charging again to 70%, some apps no longer invite to let etc.
With the new battery is working again everything without problems, this holds with moderate usage (few calls, surfing something wireless, take a few pictures and look) for about 2 days.