OnLive used about 1GB per hour at 720p. Usage caps are stupid and so is Comcast, and it sucks that they're the only choice in some places.
If it were my only choice, I'd hold my nose and upgrade to business service or whatever is unlimited, because 1TB isn't nearly enough data for my work and play.
Comcast/xfinity is my only choice at the moment. Unlimited data from Comcast is $50 more per month, I have never had more than $20 in overage charges so paying for unlimited doesn't make a lot of sense for me. Hopefully when 5G cell service comes to the Ann Arbor/Saline area I can at least have 2 choices. Data caps suck.
I have the Xbox game pass and I have to be careful how many games I download. A 50GB game like Halo would eat up 5% of my data for the month.