It feels kind of bitter sweet getting this update.... I've been waiting for this update for such a long time that it almost seems cruel to release it now. My S5 has been one of the best phones I've ever owned, hands down. So it's sad to finally get an update that makes it feel insanely faster/snappier after I've been dealing with a failed Gyroscope. So no auto rotate and I've been living with a screen rotate app to manually turn the screen for videos, reading, ect.
Anyway... in case anyone was wondering, the 6.0.1 update is nothing short of amazing. Before the phone would jutter if switching between lots of apps or would sort of sit there to exit them. Typing sometimes would delay a little bit but then type suddenly what I had pressed. Now it is fluid, instant and I can switch between apps within a 1/4 of a second and consistently 20+ times with no sign of slowing.
I'll have to wait longer to see if the new deep sleep and app state really helps with battery life. Otherwise if there are any hold outs there with an S5 who might have one sitting in a drawer, dust it off and update it. It feels like the difference between a fresh Windows install without drivers and then suddenly you install the video/chipset drivers to awaken the system.