TOD/beneficiary deeds are an excellent way to avoid probate time/costs. I have never heard of any estate taxes being imposed against them (but I suppose it's a good idea to double check) because they are not considered to be part of the estate.
No...
"Inheriting a POD doesn't exempt the account from estate tax, either. For the vast majority of Americans, though, that's not an issue: as of 2013, only estates worth more than $5.25 million pay estate tax. And even if the deceased had that much money, it's the estate that has to pay the bill, not you. However, the executor can legally tap your inheritance to pay the tax, or the deceased's other assets, if necessary."
OP, you need to consult with an attorney in the states where you own property and have intent to leave to your children.
They can best outline the laws and nuances of inheritance and estate issues.
Please seek the counsel of someone who absolutely knows what they're talking about.
Leaving something to a spouse differs from leaving something to a child.
As you are probably familiar with already.
POD is part of the estate, it just determines how the transfer is done, it doesn't shield assets from any estate tax calculation.
Talk to an estate attorney in CO and TN.