Just to clarify what I was saying, I have the gourmet system but I was using the standard normal grate insert, not the cast iron. The normal grate did get badly discolored but mine had started rusting previous to using the vortex on it. The vortex definitely discolored the grate to a reddish color, indicating heat damage. I don't really care. The gourmet grates are pretty sturdy but they definitely aren't stainless (my center sectioned rusted over almost immediately after purchase, but I'm sometimes lazy about cleaning my grates right after a cook). I use the cast iron searing grate most of the time.
my center sectioned rusted over almost immediately after purchase