I have purchased a bunch of batteries from ifixit but lately I have had a rash of bad batteries that did not charge when installed, or would only hold about 20% of the rated charge. On the last install on a 2016 Macbook Pro Retina Touchbar it was more than just a minor inconvenience given how many screws and connectors must be removed and reinstalled. I ended up taking the laptop to a local repair shop who fixed it for not much more than the cost of the ifixit kit only.