I bought the 6+ because I didn't want to wait for supplies to catch up to demand. When I walked into the store, I wanted to walk out with a new phone... not an order which might show up in a week. All AT&T stores just had the 6+. In the beginning I went through cycles: OMG this is huge, how baby-toy-cute is that 5, how am I going to hold onto this monstrosity (6+), how archaic is this brick with square corners (5).
Now after owning the 6+ for a number of months, there's really no way I'd want to go down to a 6, and def no way I'd want to go down to a 5. I've found I just modified the way I hold it for certain functions. I don't text a ton, and when I do 2 hands are used. When I surf on the train, bus, plane, etc., I've found that I have no problems with one hand operation, as like I said, I just hold it differently. I have thick hands, but short fingers (compared to peers). If you can envision the way a crane operator moves over a shipping container dock, that's sorta how I hold it. Thumb on bottom, two fingers up top (middle and ring), with the index finger moving around to select. Index moves up and back for viewing. Somehow I've made this work in the most awkward situations (answering phone while riding bike as one example).
Interesting thing is that now with the 6+ I barely use my iPad (3rd gen) at all. Suprisingly, I also barely use my relatively new MacBook Air. The 6+ portability, but bigger size just seem to render all other portable network capable devices as unnecessary. Certain websites I cringed when surfing them mobile, and would wait until I had the MBA to use them (e.g. job sites), but with the 6+ I only have to wait when I'm needing to attach documents (e.g. resumes).