The downside to concrete countertops is that concrete is porous and needs to be resealed regularly, otherwise it's mucho unhygenic. FWIW, we went with engineered stone in our kitchen rehab a couple years ago. It's 97% quartz, which is something like the second hardest stone after diamonds, or something like that, and 3% acrylic, or whatever the medium is that binds everything together. The advantages are that it's harder than granite, totally non-porous to the point that you can actually cut raw chicken on it and clean it and there won't be any dangerous bacteria left behind in the pores, becausenonporous. It never needs resealing and cleans up with plain water and a mf towel, or soap and water, or something like windex. The disadvantage is that the look is very "regular", in other words, you don't get the cool graining that you can get with some granites. Ours is a uniform speckled surface. We actually like it better that way, but everyone is different. Just my $.02 on countertop surfaces. We did months of research so it's nice to share our findings, FWIW...YMMV and all that.