The Schott Jena glass must be a much harder higher quality than the run of the mill glasstop material used in the USA. I was told that Schott makes all the cooktops in Europe and I had thought they make them for America too-but I guess Corning makes the most for America, although, as Mary Anne said, she bought a stovetop with Schott glass, but she did not say what brand it was.

I use all types of pots, including cast iron which I brought from America, but the most effective are the multi-ply or tri-ply because the heat is distributed evenly over the whole pot--not just on the bottom. If you ask me there is too much heat concentrated on those sandwich bottoms. I do not like them because they burn food too easily.

In Europe the best brand is Spring from Switzerland (too expensive but once used you never want to use any other and you have it for life), and Berndes has started a new line called Berndes TRICION®, and then Rösle has a new multi ply. Is not All-Clad a multi-ply?

I have used copper and copper bottom Revereware on my Schott stovetop with no adverse effect, but I can imagine that is you would let the water boil away or you were to put the burner on and forget to put food in the pot, the copper could very well melt- it is a soft metal. So caution is in order for copper. I also use pots which are not the exact size as the burners, but I use multi ply pots mostly (not always).

I would advise to buy stovetops which employ German made glass from Jena, Germany. As Mary Anne said- Schott.

If you take the time and look around the 'net, you'll see that there appears to be a ton of complaints and problems with these stoves. FWIW, after doing much research, I can emphatically say that YES, there ARE differences between the various manufacturers and brands out there. I have found that genuine Ceran holds up the best for daily wear and tear. The other manufacturer, EuroKera out of France, is the stuff I've had the most issues with. Scratches, small pitting, streaking, and cooktop fading are just a few problems I've encountered using with these cooktops. You easily easily identify if it was made by EuroKera simply by looking for a small "k" symbol in the upper right or left hand corner of the glass near the back splash. It seems the majority of ranges built in North America are being made with EuroKera, whereas the European models are built using Schott Glass. I'm sure there's some trade agreement or cost-cutting involved here somewhere, but I am of the opinion that EuroKera is indeed inferior material and higher maintenance.

My last smoothtop range was a Whirlpool Gold, with the glass being manufactured by EuroKera. The instruction manual was very explicit when it stated the cooktop surface MUST be cleaned after each and every use--even if you were just heating up a can of soup or boiling water. Not only that, but the manual also recommended a monthly treatment with something called "Cooktop Protectant" that was made especially for Whirlpool, and (supposedly) left behind a thin film on the glass that helped repel stains and residues. I guess it was meant to perform kind of like a car wax? I don't know if it worked or not, since about all it did for me was make the glass surface extremely slippery and left a swirly residue in its wake, which only served to make the stove look dirty again--go figure...