I’ll cut to it and let you know that you’re going to be told that quartz isn’t an appropriate splash to put behind your range and that it won’t withstand the heat. As to your seams....if that’s all the fabricator can do with the material you have, what are you hoping for? It likely depends on whether your quartz has veining whether those seams will look okay, and that will depend on the pattern match.

I was told by the fabricator that because I’m using electric stove would be no problem to use quartz.. now with you saying this I’m having doubts. Maybe I’ll have to scrap that idea then and think of something else.

Do a search here and see what others have to say about it. It’s often discussed and I’m no authority on the subject. I’ve read enough to believe that I personally would be very unlikely to try it. You may assess the risks differently than I would.

The seam placement is fine. Check your appliance manufacturer's installation instructions for proper clearances before installing any splash please.

The seam placement is NOT fine.

The seam left of the sink needs to be moved to the square inside corner, just as the other seam is, OR the corner needs to be rounded to a minimum radius of 3/8", in order to prevent a potential failure point (crack).

@Technically Countertops im not following what your saying, you are talking the bottom seam correct? Do you mind posting an image where the seam should be moved to? thanks!