I've used the Galaxy S6 Edge+ and I can safely say it's better than the iPhone 6+ that my G/F owns. The screen is MENTAL! It looks like you're looking at a photograph, it's so dense, so high resolution, the colours are much better and it gives you an option of saturation or realistic which is great. It's easily twice as bright as the 6+, you can shine a light directly at it and you can still read it perfectly... just crazy how good that screen is. I love the black blacks, when you directly compare the iPhone to that, you notice all the light bleed of the LCD.
I tried the loud speaker which was much louder than the 6+ and I also tried the camera, which took much better shots.. though that isn't surprising at all considering it's a larger sensor, better lens and higher MP count and it was also faster.
Apple have real competition on their hands with Samsung, I'm not gonna buy one because it doesn't interest me, but man, one hell of a phone.
+ Android didn't lag on it one bit and the new Touchwiz looks like Stock Android, but you can just use launchers on Android any ways.
For me though, I'm waiting to see what Microsoft and Apple do, still holding out hope for a Nokia 1030.