20 - 30 minutos
The phone was shutting off at 50% charge.
A little longer than 15 minutes, because I took my time. The only tricky part for me was putting the memory board back in and getting it aligned.
It's easy. Just take your time! Also, the protective sticker over the one screw you are not to remove, forget it...it tore on me. I just ripped off a tiny piece of the replacement battery sticker(it covers the glue strip), and placed that on the screw before I secured the ribbon that covers it. I'm guessing the screw was covered as to not short out the ribbon. Either way, no worries.