I also think the Z3 is the pick of the phones at the moment.
I just got a Samsung Tab S 8.4, my first Samsung device.
Great hardware, but Android OS is very different from the Nexus 5 (not in a good way). Heaps of bloatware.
When you click on the apps page/folder the apps are in random order, is there anyway to arrange them in alphabetical order like the Nexus 5?