I'd take some discoloration vs. Any nonstick poison coating on a conventional modern baking sheet. You could also use parchment paper or silicone baking sheets (if you trust the silicone) to prevent stains on the pans. 

I tend to not care too much about stains on the enamel. But if you do, the only way to solve this issue is to spend a lot of money. 😅  

 I avoid nonstick coating like the plague, don’t worry!