Go with the Grey tile.

The cabinets appear to have a green cast to them in my computer, and the white tile appears in my computer to add a different neutral -- different with respect to both the cabinets and the granite. I would recommend that you ask the tile store to recommend a designer to come to your house to view these colors in your home -- a miss is as good as a mile. Glass tile is more forgiving than ceramic or porcelain -- it reflects the colors in your cabinets and backsplash. Also, the smaller the tile the more difficult it is too clean, but the greater the opportunity to make colors work together. Smaller tile permits more grout color, and if the relationship of your grout to your tile is chosen well -- it can make all the difference.

this is the other side - better lighting in this picture. Obviously, before hardware and appliances....

The cabinets are bright white........I see no problem with a white subway white grout. Bring SEVERAL samples home and try in both daylight and evening light.

I also agree with using white subway tile!

Have you tried a light gray subway tile? Then you wouldn't have to worry about matching your cabinets, and also you wouldn't create a focal point as you might with the dark gray. I'd match the light gray in the counter! And then, add some splashes of color such as a Kitchen Aid mixer, decorative platter, canisters, etc. Good luck!

Choosing a backsplash can be overwhelming! Here is
a great article: A
Backsplash Guide

Some good ideas... thanks :)

what do you all think about this tile in my kitchen?

I love it - but not sure how it would work out in my own space....

Stick with what you have unless it does not have an outside venting system. With this one you will lose some cabinet space too. I like a regular size white porcelain subway with a light gray grout. You will have a lovely kitchen.