I bought the battery (11.1V) in September 2012, at the time he held with regular use of e-mail, streaming, Internet surfing, Office 1.5 hours. For this must be said: Just as you should deal with each battery, I have this always completely discharged and then fully recharged. Meanwhile (Feburary 2013) maintains the battery with the same use as just described hardly 45 minutes. This means that the battery power has been halved in less than a half a year.
I have made contact with Net-Electronics and asked for exchange or refund. In the first message I received no reply, on the second I had to wait 10 days. Said response did not include a single personal lodged at my request (salutation: "Dear consumer, estimated Consumer"), but consisted only of a detailed (5 pages) instructions for the battery.
Two stars for the rapid exchange and because the battery has not completely given up the ghost, 3 star deduction for the quality, the waiting time for a response from Net-Electronics and not user-friendly response.