I am not comfortable with heavy cast iron on glass tops.
Nor am I.
About ten or eleven months ago we bought a new electric range, near $2,000.00, bells and whistles and glass top and all. Neither of us cared much for electric stoves but the house did not have a gas line to the kitchen. The instructions stated "Do Not Use Cast Iron unless you are extremely careful! Buy special Pans" etc.
Over a period of time, we had some problems with the stove. Finally about two months ago, I had the stove removed, paid a plumber to run a gas line into the kitchen, bought a nice gas stove and the first night, out came our cast iron skillet. No problem, no worry, and no need to be careful about scooting a cast iron pan from one burner to the next.
No more glass top electric for us... ever!
L.W.