Thanks for the great sales pitch Ken.
I can also speak from experience of use (well, not me personally on the end of the brush/roller) on precast concrete, although not so many years ago.
The building came up well (can probably source picture if anybody desperately wants one), but we did have problems with dark stains leaching / reading through the paint system. So you need to know that due to the nature of the paint system, it will NOT necessarily hide past sins on an existing building like most organic paint systems do. If you have staining or soiling on the masonry building, then you need to clean or otherwise resolve that problem before you start applying the Keim coating.
But this won't stop me from proposing the product whenever I find a suitable candidate.
david