I am on the Nexus 6 (sorry, not the 5). Everything from Lollipop still works, some of the new features aren't fully in yet but many are there to play with, such as permissions, etc.
Just installed it. Most apps work, Sygic doesn't. FIOS Mobile (the mobile video app) doesn't work either, not to be confused with Verizon FIOS (the app that allows you to control FIOS features like call forwarding) does work.
I haven't tried Waze, so will leave that to others. Battery is very on par with 5.1 so far except for when it does the deep idle thing, then it basically doesn't drain at all.