The camera is a real winner on this device.
The strengths that stand out to me on the S6 really are:
1) Screen - sublime to use. I really can't use any other screen. Everything else looks poor compared to it, including the One Plus and the iPh 6. And the dimness and brightness levels really take them to their extremes, making the S6 very usable both in the dark and in direct sunlight. Bright sun in your eyes? No longer a problem.
2) Camera - Fast. Easy. Reliable. Quality. Sounds like the iPhone camera. And it is the iPhone camera, but even better in low light and even better for zooming into details. Big win here. And double tap home to quick launch the camera at any time? Super useful. The front camera deserves some mention too. It's a healthy wide-angle 5MP camera. The iPhone's 1.2 MP camera is embarrassing next to this.
3) Call quality/GPS strength - Instant lock and ready to go. Never a problem with calls or signal strength. Just easy and reliable to use. Again, very iPhone like in this area.
4) IR Blaster - I can control my TV and the cable box from my phone. I can see the guide right on my phone. It's faster and easier to use than the actual cable remote. And it was extremely easy and fast to set up. Love this feature.
5) Quick settings - I think Touch Wiz's implementation of the Quick settings is really the best. It's narrow and doesn't take up any real space. For comparison, Sense's pull down quick settings is a disaster. Ugly, overcrowded, and messy. Just gross. To a lesser degree, so is the stock Android pull down quick settings. Not as messy or ugly, but just crowded. Also, what makes Touch Wiz's implementation better is that it only requires one pull down, versus two on stock. This makes a big different when you want to quickly access or toggle something. And the fact that you can swipe to a second page full of second tier toggles? Fantastic. My only one gripe is that you can't remove "S finder" and "Quick Connect". Such wasted space.
I also think it's worth mentioning here that even within the main Settings menu you can edit and set up favorite settings at the top (up to 9). It's a lovely feature.
6) Nifty TW features - split screen multitasking, I admit, is used rarely. But in those few times you need it, the feature is very handy! I've used it only a handful of times, but found it very easy to use and helpful. I rarely minimize my apps though with the corner-pull down move, but that's kind of cool too.
7) Great speakers - Pretty good quality and loud! Very easy to talk to someone on speaker or to use it for Navigation.
8) Gorgeous design - The gold is a real winner. The gold metal trim around the device is lovely. Very easy to be enamored with this device.
9) Quick charge / wireless charging - I haven't had the pleasure of using wireless charging yet, but look forward to it once I decide on a wireless charging device. But Quick charge is a real win. It always surprises me how quick it goes. Moments later, I'm back over 50%. And if I wait a bit more, my phone suddenly lights up and I'm back at full capacity. It's that fast that you just kind of forget it was charging and suddenly you're ready to go another 24 hours again.
The rest of the stuff is just good. Like fingerprint scanner. It's okay. Just as good as iPhone's, I guess, which means once in a while you'll get the mis-read. TouchWiz is also just good in terms of how cleaned up and fast it is. No device is lag-free, but they are indeed very rare. I use Google Now Launcher and Google keyboard. Both great. Wish there wans't so much bloat, but once disabled, you forget about 'em. And lastly, battery life, eh, just good. Good enough to last a work day and then some if you push it into Power Saving mode. Wish it was longer, but what can you do. Thankfully you get Quick charge and once I get a wireless charger at work and at home, I'll be topping it off whenever it's idle anyway, so no bigs.
Overall, this is becoming a great device. Everything is either good-to-great; nothing really damaging or bad about the overall package.
And that's saying something.