Disclosure: I don't have a 6 or a 6+ but do have an interest in watching videos on them if and when I get one. So... I went into my local phone shop and played around with both models. I checked out the video players side by side using the trailers for the Hobbit and Lego movie. I put both phone to full brightness and played both at the same time. There was no comparison. the picture on the 6+ was incredible. In fact I was really disappointed with the picture on the 6. It lacked detail and was flatter in comparison. the extra DPI on the 6+ makes a huge difference. It's not a huge test or even very thorough, but this was a real world side by side comparison and the 6+ won convincingly. Just thought I'd share in case somebody is on the fence about which to get and likes to watch videos on their phone.