Some questions about MI 5s

i've been debating whether to buy MI 5 or MI 5s, since the price in my place is about the same.

1. How is the audio quality through headphone compared to MI 5? Gsmarena review said that the quality degrade with headphone. I'm not an audiophile but audio quality is the most important thing for me.

2. Screen Durability? Some people said the phone has dragontrail and experience no scratch, while others said their screen already scratched in a short time

3. How is xiaomi support for the phone? I heard the phone got little support compared to MI 5. Will xiaomi support the phone for at least another 2-3 years?