Personally, I'm not a fan of thicker, more massive grates. I don't care for CI grates either. I am not looking for the grate to retain lots of heat when I grill, nor do I care for the larger, wider grill marks of CI grates. (I like grill marks but think too much emphasis is placed on them, by and large.)
I replaced my grates with S/S grates because of the rust factor.
My two cents.