The only reasons why you wouldn't buy this phone over the iPhone 6 are your own insecurities.
After a couple of weeks:
Battery life is unbelievable. I get 3 days of usage with it. It's not extreme usage (mainly Twitter, email, spotify, YouTube, ...) but a decent one. Simply the best mileage I've seen ever in the smartphone category (we all miss that Nokia 5110).
That big screen is really differential for things like email, Twitter, reading, writing (I'm writing this post with it, actually), playing.
The camera is great, although I would not say it's incredibly better than the iPhone 6's.
It fits in all pockets. Granted, it's not the smallest thing you've had in your pocket but you can definitely carry it around comfortably, even in jeans.
It's very difficult to operate with one hand, but you adjust fairly quickly. It has not been a major annoyance so far.
It looks ridiculous. It does. And this is my major concern. But I'm betting on these things to become acceptable as the number of people carrying them increases, just like it happened with mobile phones long time ago.
If I had to take the decision again I would go for the plus. If you doubt, go for the plus.