Jury is still out on my end. If I'm honest I need to say that it seems marginally slower, and sometimes straight-up unresponsive. Unfortunately my stability has been erratic under KitKat in general, so it's possibly specific to my phone. Some days under KitKat the battery did great, other days I'd burn through 70% of the battery in an hour with the phone in my pocket. Like La Trotter I largely like the layout, but conversely have yet to discover something that makes this better than before (except for a "restart" option when powering down - which I don't think I had w/ KitKat). That is hilarious in itself because I've been SOOOOO looking forward to Lolipop. I can definitively say that if my experience doesn't somehow (miraculously?) improve between now and the release of the LG G4 I'll be jumping ship to it.
Looking forward to other opinions or observations.