I just got back from Best Buy and was able to spend some hands-on time with both the S6 and S6 Edge. Coming from the Nexus 6, the size difference is a bit of a shock, but both devices felt extremely premium. If you're coming from a phone with a curved back, the flatness of the S6/S6 Edge will take some getting used to, but there's no denying just how incredible these devices look and feel. As far as the Edge goes, the sides are slightly sharp, but I'd have to say that I wouldn't let that be a deterent from buying the device if you like everything else about it. The infinity pool look is striking in person. If you want a phone to turn heads, this phone will most certainly do that. Then again, so will the S6.
The display on both phones just isn't fair to other mobile displays. Absolutely puts my Nexus 6 to shame. The Edge has this slight distortion depending on what you're viewing on the screen that gives off this really cool effect. If you've been on Lollipop for awhile, specifically stock Lollipop which utilizes left to right gestures, this phone feels extremely natural to do that on. Not sure if that was intended or not, but it's going to go a long way for me when it comes to usability.
I'm sure I don't need to tell you how quick the camera is. As we've all seen, the quality is going to be on par or better than both the Note 4 and iPhone 6 Plus. In fact, I'd probably rank it ahead of both given that it takes the same ridiculous daylight photos the Note 4 does, but is vastly improved in low light to compete with the 6 Plus. If the camera you have on your phone is of paramount importance, you really can't go wrong with the S6.
Tested the fingerprint sensor---it's milliseconds slower than the iPhone. I tried 10 times from various positions (screen on, screen off) and didn't get it to fail once. I'm going to guess moisture will stop it, though, just like on the iPhone. Speaker is plenty loud; couldn't tell you about the clarity given that it was in a crowded store. Too many people huddled in the Samsung Experience wanting to look at these things. They've got a smash hit on their hands.
I haven't been this excited about a phone in a long, long time. I preordered the S6 Edge in Black Sapphire last night and getting to play with it today more than reinforced my decision. We may be looking at the class of 2015 already, folks. Of course, that is, until the Note 5 comes out. I'm going to guess that it will be the most ridiculous phone we've ever seen.