Spouse at Facebook. Which health plan to choose at Amazon?

I have recently started at Amazon and spouse currently works at Facebook. I'm currently added as dependent on my spouse's health plan.
It's now time to pick my health plan at Amazon for next year and have few Qs.

1. Which health plan is better.? We have one kid.
2. Should I not take up Amazon health plan at all and just use Facebook insurance?
3. Is it better to use Amazon as primary insurance and use Facebook as secondary or vice versa?
4. Are there any good perks at Amazon health plan not in Facebook and vice versa?

We both are in relative good health wise and just use insurance for occasional doctor visits for yearly checkups and the like.

Thanks for the help