I've used them on
my Ultramarines and on my
Space Wolves. Ultramarines are the separate pad-shaped curved symbols that glue directly onto bare pads and also the separate set of flat vehicle-sized U symbols, both of them were off his old Shapeways store using frosted ultra detail since he olnly sold through Spaheways back then, the stuff he prints and sells direct is likely just as good.
They work fine, but they're very thick, much thicker than molded plastic pads.