"own State's coverage is not good, or basicallly non-existent as soon as we leave our home state"
I'm not sure this statement is 100% accurate but I just retired and looked into this over the past year as I lost my employer healthcare and I will be travelling out of state.
Here in NJ (and I assume throughout the US), the healthcare provider is state centric, so you get all the health benefits as long as you are in your home state. When you venture out of state then you are covered for all emergency situations but not for "regular" non-emergency procedures.
Out of all the insurance companies operating in NJ, I only found 1 that offers out-of-state services equal to home state services BUT the premiums are much higher.
So to answer the OP, you are covered when you venture out of state
but with reduced services. Always check with your insurance company for the facts.
Gerry