Fwiw, I just mixed faux-marble quartz (Lagoon) with a Carrera backsplash and at least in it's pre-grouted state, I'm really happy. It was hard for me to find a backsplash that worked well with the grey-ish tones of the Lagoon, mostly because my cabinets are painted taupe. Anything that "matched" the cabinets seemed too brownish for the counters. The Carrera blends the two perfectly. I think it also works because I wound up using a very small-scale herringbone pattern, so the patterns in the marble tiles are less pronounced. Fwiw, I don't see the calacutta tiles that the OP posted working with a greyish quartz that's similar to Lagoon, and I'd also be concerned about pattern overload with a subway tile. But having worried about the fake-next-to-real problem, I wanted to at least add my experience that it can be done. One of the prettiest kitchens on here, done by a pro, is GW user @kompy, who used a different marble subway with Lagoon counters, and it looks stunning.

didn't have time to read all the answers. I have no backsplash and have never regretted it...been over 6 yrs. It is painted with BM matte...which has ceramic in it. It is as beautiful now as it was when first painted. I love the fact that I can showcase other things ...art etc in my kitchen and no competition. Also if I ever want to change it is as quick as a paint brush...expense is minimal..paint only ! All in all I think it is serene as you point out . Here is one pick. Since I have a lot of high heat cooking in my kitchen..built in deep fat fryer as well as gas cook top I can definitely speak to the longevity of paint only. c ( more at this album )

I had a kitchen countertop with the built in 4" backsplash for almost 20 years. The wall above the small splash was painted in a washable paint. I never had any problems with it. That is a perfectly acceptable way to go. I recently changed out counters to a new quartz and did do a simple subway backsplash. I like it very much and it was not too expensive. The tile was about $230 and I installed it myself. My neighbor was charges $400 for her install of the same tile, but that is low for a backsplash install.

You didn’t know what you didn’t know. And that's pretty much the rule for every project where a home owner works with a professional. If the home owner knew everything, they wouldn't have to hire anybody. If the professional asks an ambiguous question, and then deliberately skips the industry-standard step of visually confirming the layout with the client, then it's inappropriate to blame the client for not communicating well. This is a question that comes up with literally every single job the fabricator does. They should know how to verify instructions. We have had all sorts of counter tops installed over the years. Every single time, the fabricator would come to the house to do precise templating. And then they'd require that either the home owner or the general contractor sign off on the template before they'd make the first cut. These processes are in place exactly to avoid this type of issue. Yes, there have on occasion been mistakes. But when that happens, the professional eats the cost or finds a way to fix things that is acceptable to all parties.