iOS 8 update download takes forever

I've been trying to update my iPad thru iTunes for two days. Every time, it estimated 30+ hours to download. I left on Mac on, but eventually, it got network connection error and I had to started all over again. Tonight, it's even worse, it's estimated 63 hours to download. This is the worse iOS update I've experienced. Previously it could be slow, but I can usually get it done for a couples of hours. This is just insane. I understand the severs are busy to deliver these big files all over the world. But iOS 7 was a pretty big update, I was able to upgrade pretty quickly. Seriously, can anyone from Apple can look at the server log and make sure there is no oversight.