MacBook Pro 15" Replacement battery

Mi Problema

Had to change the battery in my 5 year old MacBook Pro 15"

Mi Solución

The service and delivery speed was top notch!

Installed the new battery I got from Ifixit.

What bothers me is that the new battery is not as good as I expected.

It drains fairly quickly, almost the same speed as the old one.

The situation is somewhat getting better.

Mi Consejo

Is this normal? Did I do something wrong when charging for the first time, etc. etc... Or are those batteries just some second grade product?