I am having a carrera marble piece fabricated to install on an island. When I asked about sealing, they said it would be sealed with a GranQuartz product and recommended using 113M 3-1-spray (also a GranQuartz product) that supposingly cleans and seals at the same time so that every time I cleaned the top, I would be re-sealing it. I tried to search on this forum to see if anyone had anything to say about this product and was not able to find anything. When I mentioned the 511 Porous Plus to them, I was told that that was just one of many types of sealers and they had good success with the GranQuartz product. Have either of you (or anyone else out there) heard of this product? I did a google search and did find it for sale. The cleanser was advertised as a ''cleaner/polisher/protector''. If I wanted to re-seal w/ the 511 Porous Plus, would I need to strip the old seal off or could I just put over? Also, if not the above, any other cleaning agent you could recommend for marble? Thanks!