1. Back up your claim
2. Back up your claim. I'll do it for you. The method used is the same. The sensor on the S5 and the camera+flash on the 5s measures the change of color in your finger due to the blood flowing in and out. Same method used at the hospitals with that gadget that clamps to the tip of your finger with a light in it.
3. Once again, Samsung rushed 4K video recording to say they did it first. They can't even include stabilization yet. Why have that much detail and resolution if the video is ruined by all the shaking? Again, you will be limited to who you can share the video with because 4K TV's isn't mainstream yet and most computers cannot render 4K smoothly yet.
4. That water and dust resistance caused the device to be bigger. Not worth the .1 inch, IMO.
5. The ROM size for the S5 is now 8GB. Talk about bloat.