I have a mid-2012 MBP 13-inch and it is about time to change there battery as it has warned me by saying "service battery." I am very confused as to what to do now though. I found an IFixit replacement battery for $89.99 but I'm not sure on the quality of the battery. if anyone has replaced their battery with an IFixit one, could you let me know its holding up and how long it lasts? should i get apple to replace it for $129 or replace the battery myself with the Ifixit one?