I didn't really get to see either device, I just went in, told them which variant I was interested in (Black 64GB Edge) and we proceeded upstairs to switch my service over. Started playing with it later when I got back to work and the S3 lost service.
I can't really compare battery life to the S5, plus with the first few days you tend to use the device more than normal so I can't say too much on it. One thing that does annoy me is that the included 'fast charge adapter' is too darn fast. I'd normally chuck the phone on charge at night then pull it off in the morning, but this thing will give me 50% extra battery in something ridiculous like 20 minutes. So I may revert to slow overnight charging by connecting it to my PC (which any of my active Steam friends can tell you is on 24/7).
Couple of points so far:
Dragging icons from one home screen to another seems easier with the defined edges,
Pressing buttons on the edges sometimes takes a couple of attempts.
I really miss the dedicated menu button on the left of the physical home button, which is now a multi-view/recent apps task switcher doodad. I'm sure there will be an app to change it back to my preference sooner than later (haven't looked yet).
Who uses back pockets these days? This isn't the 80's.
Need my blender for daily smoothies, so I'll leave that to the experts.