I do not have either, but I am fairly certain you will scorch your quartz using it as a backsplash behind a gas stove, especially with that ledge. Look up quartz backsplashes burned online. You might want tile there instead. Quartz is made with acrylic/polymers so they brown. Granite is plain stone so it does not have that issue.

This is a great point!! Thank you!!!!🙏🙏🙏 what cooking range do you have? Any recommendations?

I have a Wolf natural gas range it is puts out the heat. Don't do quartz for the backsplash.

I have marble and its held up great.

I literally have a 36" gas stove top that came with the house. It is Dacor or at least that is what the pop-up down draft behind it says. I think they are the same brand. I hear Wolf is a great brand but I don't know anything about Ilve. Did you compare online reviews? I am assuming you like the look of the black one that's why you are not going for Wolf automatically??? Sorry I am no help in your decision making.

Online it says most of the time the damage is from the vent for the oven being located in the back, but I know it happens from flare-ups in a pan too.

"what cooking range do you have?"

Have you considered induction instead of gas? I made the switch to induction earlier this year and couldn't be more pleased. I have a Wolf Professional series induction range.

Wolf and Miele have 36" induction ranges. Miele offers a version with a water hookup for steam in the oven.