These seem to be the perfect combination of top/bottom parallel clamping and using cauls. They use shop made cauls as part of the clamping mechanism, so you get flatness and it prevents boards from popping up at the seems under compression.
I've been waiting for these to go on sale and will probably get at least four. Seems like a no-brainer considering the great design and how much cheaper they are than good parallel clamps.
I go in with caution because having bought many of Rockler's "inventions" and being greatly underwhelmed due to low quality control and under-performance, I've grown to be wary of their house brand.
However I'm fairly certain, they didn't invent, nor manufacturer these. We'll see how it goes.
Anyone have these, already?