Because how many tens of thousands of those Dreamboxes were produced? And how many similar products use the same mainboard? Compare that to the number of Sam systems produced... I can't see the link myself (blocked by my work server) but if it's like the Dreamboxes I have at home, it's a 350MHz PPC with 32MB of RAM soldered to the board, practically no expansion possibilities, no storage controller (either IDE or SATA), and a limited flash area for the OS. I hardly think it's comparable to the SAM, even if the Sam is underpowered...