I picked up some pavers from the local brick/masonry supplier a couple nights ago to do a couple small mockups of color. I noticed that on some of the pavers, the tops are somewhat porous - along the lines of a regular 8x16 CMU cinder block (in places). Is this normal, or is this a quality issue where I should look elsewhere? I have limited sources here, but putting in an expensive patio only to have it look like #$%^ is much worse than going to some extra lengths to find quality products. Your thoughts?