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I personally would never trust a battery that didn't come from Apple.
Generally I would agree, but the design of these batteries is really bad.
Yesterday, I went into the Apple Store genius Bar with three Apple factory batteries and all were determined to be shot. And they didn't have that many cycles either. There was a woman at the bar with me who was only getting 7 minutes of charge from her battery. Do not spend full price for these batteries -- you are not getting quality.

Thanks to kellen for this link to OWC where these batteries can be had for $59. I ordered one yesterday, and hope that will hold me out until the MBP 13 gets updated.
 
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