Our top has been fine in the 3 1/2 years we've owned our Sunseeker, though it always seemed to be in a bit of a bind. We had to push a bit aft on the top to get it to seat. It has small rubber pads in various locations, so there's never a metal-glass contact.
When I rebuilt the countertops last winter with Corian:
(More pics of our Sunseeker mods at
https://pbase.com/brucemac/2015octsunseeker)
I found the installer hadn't squared it up during the install - they apparently tossed it in the hole & ran the 4 screws in to mount it. I re-aligned everything, and now the glass properly drops into the opening. It didn't rattle on my last monthly maintenance warmup run - if it did, there's plenty of other noises to mask it.
Our old Four Winds didn't have a stovetop cover - if you are concerned about yours breaking like the OP, it can be removed. Open the folding glass top, remove 2 screws on both sides of the upper frame. Gently lift the assembly out, then unbolt the hinges from the frame. Set the frame back in place and reinstall the screws.
We'll continue to run with ours installed.