Was unable to get the gpedit to work.
However, I was able to test "metered" by directly tethering instead of tethering to the router. Learned something shocking.
The only difference a metered connection seems to have made is that I get a notification to "Exit" OneDrive to save bandwidth. OneDrive does not automatically stop syncing like on Windows 8.1. It cannot be configured to stop on Windows 10. You have to manually exit.
As far as Updates go, the computer installed 2 updates without asking while on the metered connection. ?!?
I certainly hope Microsoft has plans of implementing this properly before final release. I know they said Windows 10 machines would require Internet access, but to use up a person's metered data allotment against their will is just plain ludicrous. Yes, I am providing this as feedback, but thought others should be wary of this, as you may be on the road, use your precious cell phone data to tether, and end up downloading several hundred megabytes of updates unwittingly.
This is just about enough to force me to go back to 8.1. I am loving 10 otherwise, and am enjoying giving constructive feedback to Microsoft. I'm just not sure my data plan can afford the constant forced updates, since my data plan is the only Internet I have while at home. Something I'll have to consider over the next few days.