20 - 30 minuten
I fell for one of those "updates" that totally bricked my 3GS. Did the update, restarted it, then it died. I held out for a couple days before getting another idevice, but the 3GS was faithful so I had to hang on to it. I was not even getting it to apple screen - and it was unlocked..! (That's the last time I update the 3GS - EVER!)
Repair went smoothly, especially since it came with all the tools needed to perform the operation (very appreciative). I wasn't trying to speed through the operation, so it took maybe 20-30 mins. It gets easier, as this is the 2nd battery replacement I've performed. First time was also the result of the first "battery management" update in (2010/11?). Like I said, it's faithful...
iForgot to use my last iFixit coupon! Price was still very reasonable. I see a couple other providers coming out with unlimited everything plans. Now that I have an unlocked iPhone, I might give them a try and look at getting rid of my current carrier, As Their service is getting Terrible...