Perfect! not as difficult as it looked first, especially with the proper tools. To take the batteries out the alcohol (I used ethanol used for cleaning purposes) works like charm. I put a few ml in nearby the batteries, waited maybe 20min and was able to pry them out easily. Tried before without the alocohol and nothing moved. I ordered the battery on ebay for 70€ and it has the same numbers and text as the original it says apple japan as well. My old battery had more than a thousand cycles after 3 years and did not last vey long. Now the software shows 0 cycles and it is charging starting at 15% and will be fully charged in 2:45h. I think apple charges 249€ for the job here in Gernany. It took me about 1 hour to replace it (with waiting).