For me, on my 6S+ running the latest 10 beta, battery life is phenomenal. For instance, today. I've been home with fair to good cell coverage, and on wireless all day. I unplugged at 4:30AM, and have been using my phone for emails, some slight texting and playing words with friends. Spent a couple hours total on Facebook. As I type this at 7:00PM, the battery is at 85%.
Now, when at work is a completely different matter. I fly in helicopters during the day, and therefore the signal is always hopping from tower to tower. I use the heck out of my phone at work, it's almost never out of my hand. On top of this, I use it to listen to Sirius to and from work, about a 30 minute drive each way. After a 12 hour shift, it's usually at 30 to 35%. Sometimes less.
Personally, I think this is great! Hope it helps.