The Gear S3 has the esthetics of a truly premium watch with advanced features built right into the watch design. That's why it's so easy and effortless to use the Gear S3. It's also built for you to go days without needing your phone or to recharge. You get to feel free with the Gear S3.
I got lucky and found them in stock at a local Best Buy after Christmas 2016.
I'm using this watch WITHOUT a Samsung phone. I'm using it with a rooted and unlocked Nexus 6 with a custom OS (Dirty Unicorns ROM). You will have to download the Samsung Gear app and a couple other plug-ins for the Gear watch to function. I'm sure the watch will work on the majority of the mid to high end Android phones.
I've had the watch for a week as of now (1/1/2017). The watch is amazing compared to many other smart watches I've tried (Huawei Watch, Moto 360, Moto 360 gen 2, Fossil Q). The Gear S3 is very responsive and crisp. I was not expecting much with the Tizen OS, but it is light years ahead of Android Wear.
The battery life is amazing. Samsung touts about 3-4 days battery life with this watch. I'm getting right at 3 days with a bunch of notifications coming in daily. When I put it on the charger at the end of day 3, I still had 22% battery left. I am averaging 25% battery usage in 24 hours. This is outstanding compared to the other Android Wear watches I've tried (see above).
The best part of this watch is the incorporation of Samsung Pay into the watch. You don't have to have a Samsung phone to use Samsung Pay. The Samsung Pay app is loaded onto the watch, even with a rooted and unlocked phone. The Samsung Pay app works on almost every credit card terminal in the US because of MST and NFC. If the credit card terminal doesn't have NFC, the MST (Magnetic Strip Technology) will still pay. I've used this on everything from McDonald's, Chick-fil-A, Walmart, etc and it works great; a couple terminals were NFC with the majority being MST. The only place I've found it doesn't work is on gas pumps because they require a physical card to activate a switch to start the process. Using Samsung Pay on the watch makes it much easier than using the phone or the physical credit card.
The only complaint I have on the watch is there are not many apps that work with the watch to get watch faces. Unlike Android Wear, there is only a couple ways to get new faces outside the Gear app and unless you know how to operate Photoshop and the Samsung Gear Watch Designer program, you are stuck with what is out there already. It would be nice if apps like Watchmaker would also work on Tizen.
I'd highly recommend this watch for anyone looking for a smart watch.