My battery lasted a few hours before I had to charge it again. I was not able to take many pictures or check my phone that often. Because the battery died
The repair was easy, following the video on YouTube that is shared on Ifixit. The most difficult part was trying to separate the screen from the case, after that everything went well.
One advice is to be very careful with the screws, some of them don't get attached to the screwdriver, so you might lose it easily. My other advice is to read every part of the instructions that are posted on the website very carefully. In addition you can watch the YouTube video as a second guideline.
Good luck with your repair, and hope it goes excellent as mine.