Super Health

Don't forget that Health helps vs magical damage aswell, and with a high health, it becomes a bit harder to Overheal you aswell, which might save healers mana a bit ;p Thanks for the thumbs down in advance

You're forgetting one very important bit in your conclusion. Health and armor are reliable. They always perform when you want them to barring certain debuffs. Avoidance, which is what this grants not mitigation, is random. You might dodge 10 in a row, and then you might take 10 in the chin and simply die. To quote a wise warrior - "It's not about how much damage you take. It's about how much damage you can take."

For a feral druid going for pure stamina, the lowly http://www.wowhead.com/?item=38376 will give 294 hp (with kings) vs 275 from this enchant. For a more balanced approach, +10 stats is the way to go.