Wow, gorgeous tile! I think it looks good either way, but the white does look beautiful.

I prefer the contrast, but I don't think you can go wrong either way.

If you do not like the white, do a light grey.

I prefer some contrast since the tile is plain. I think light grey would look better

Lovely choices! I prefer the contrast & vote for light grey. In fact, seeing your photos made me decide to do just that; we have the same sink & similar counter...just need to find tile.

Good either way

I like the white. Very nice tiling job & I love the tile. I have Encore Silver & remember having similar thoughts after they started grouting. Once it's all grouted, you'll start noticing the different shades of color & sparkle from tile to tile.

I agree, good either way. I have used light grey grout with white tile in my bathrooms and white grout with white tile in my kitchen. Fwiw, I wanted my kitchen backsplash to be more a supporting player with my marble countertops and my blue Hoosier style cabinetry standing out more. So I went with the white grout in the kitchen.

I do like how it looks ungrouted, but I'm not a huge fan of too much contrast.

Here's a pic of our grouted white tile. Mind you, ours is a very inexpensive tile from Lowe's, but I chose a light gray grout. You could do something like this or just a little darker would make the grout lines pop more if that's what you prefer.

And a little closer:

It's very light gray, but not white.

Light gray.

Thank you for all the great responses, you are all so awesome!

The interesting thing is that the ungrouted tile matches your cabinets and the white grouted tile is brighter than your cabinets. I would look at mid to dark grey or a mid to dark brown.

On my monitor, your cabinets appear to be creamy white and the countertop with brown tones. If that's the case, don't do gray grout. Go more to the light brown side. If you have some extra tile and countertop sample piece, take them with you to look at grout color samples. Better yet, bring grout samples home to see in your kitchen lighting.

Cabinets are "white dove", a Ben Moore Color

The white grout looks classic and beautiful. You have an intricate pattern - don't make it "busy".

Before you make a final decision, bring some of the grout home and make a sample board. Fasten some tiles to a board with double stick tape. Mix up the grout and apply to the sample board. LET IT DRY (preferably overnight). The color will be darker till the moisture dries out. Then see how you like it.

We decided we wanted a little contrast on ours (not white tile though). We ended up making 5 sample boards before we were happy with the color. The grout samples at the store are only approximations of the color. The real grout will look different at home with the lighting there. Be sure to look at it in daylight and with artificial lighting.

Your tile is lovely and your kitchen will be stunning. Please post pictures when you are done.