Found this while digging around.
Very efficient use of space, super small. The A4 uses a brick, an the SFX uses SFX psus
Linus was talking about the dual power brick idea, using two power bricks is too expensive. I have a 192 watt power brick and 220 watt power supply, both of them cost me $100+ ($80 for the brick and $20 for the psu). Having 2 bricks would cost you over $200, and would be counter productive. It makes it less portable. Buying just a SFX power supply is much better.