2 - 5 minutos
Never used a case because "I don't drop my phone". Well... finally dropped it from about 3 feet onto asphalt while getting into my car. Luckily it landed on the back side. Sadly it completely shattered.
I bought the clear plastic back mainly because it was cheaper than the black glass back. I also bought the pro pentalobe tool and the repair was easy. It's a little tough to get the screws all the way tightened down without stripping the screws or the tool.
I'm not sure yet but a little concerned that the clear back doesn't have the same antenna extension that the original back had. There's a little metal tab inside that seems to connect to a metal area on the original back. Looks like some type of built in antenna extender but not sure.