Downloaded and installed, whole process from download to start using about 2 hours. (I have 10Mbps internet)

One thing though. Safari is blazing fast, switched to Safari now.
Love the look and feel, though the folders' colours are quite bright, wish they can tone it down a little in future updates.

So far so good, minimal laggings (expected on every new release)
Can't tell about battery yet coz havent used it unplugged.

Almost all essential apps works without any problem (Chrome, Spotify, Twitter etc.)