I should also mention that the non-slate glass tile accents are a light tan and green and do have some sparkle to them.

Thank you nnigrt! This is the second kitchen we've remodeled in 8 years (2 different homes). My last kitchen had silestone, and while beautiful, I hated the shininess, especially when the sun hit it. I'm prone to headaches and migraines and the glare aggravated them. That and it was difficult to see the dirt on those silestone countertops. I was constantly wiping. :(

I second the matte, for the reasons nnigrt has given and also it seems to me that your previous experience nails it for you.

i have mixed stone and glass tile as a backsplash so i'm familiar with how it reflects differently.

Thank you to all who voted and commented. I'm still undecided and the voting is a dead heat between the two.

My instinct was matte before reading comments. These are all good points.