6+ - I've never pocketed a phone unless it's in my running vest & those pockets are huge. It will also fit in my running belt. Otherwise, It's always in my purse, on a table, desk at work, etc. I have bluetooth headphones. At the gym I just put the phone on whatever machine I'm using. I hate armbands - especially outside. They leave tan lines & just annoy me in general.
I've always been a 2 handed user cuz my hands are really small. I'm 2 handing my 4S. I don't text & drive, dial & drive etc. Bluetooth in the car allows me to call & receive calls hands free - as it should be.
I'm a purse carrier - this will fit in all of them including my small evening one.
This will be my main camera too - so that's important to me as well as battery life. Often we are out & about and not near electrical outlets for extended periods of time.
I think they're both great phones & this comes down to individual choice & lifestyle.