The DDC compared to the pumps you linked to have a much better flow rate.
But considering you are cooling the CPU, both cards and chipset... either the DDC or preferably the D5 will be the best option.
Both can be found
here
and
here
Edit: Heres some info:
C-system Pump (single)
C-system = 5.5 LPM
C-system + TDX (nozzle1) = 4.7 LPM
C-system + TDX + Maze4 Chipset = 4.4 LPM
C-system + TDX + Maze4 Chipset + Maze4 GPU = 3.9 LPM
C-system Pump (2 Pumps)
2x C-system = 8.6 LPM
2x C-system + TDX (nozzle1) = 5.8 LPM
2x C-system + TDX + Maze4 Chipset = 5.2 LPM
2x C-system + TDX + Maze4 Chipset + Maze4 GPU = 4.7 LPM
Laing DDC-12v (test carried out with 3/8" to 1/2" step up barbs)
Laing DDC = 7.2 LPM
Laing DDC + TDX (nozzle1) = 6.3 LPM
Laing DDC + TDX + Maze4 Chipset = 6.0 LPM
Laing DDC-12v (test carried out with modded 1/2" inlet )
Laing DDC = 12.2 LPM
Laing DDC + TDX (nozzle1) = 9.7 LPM
Laing DDC + TDX + Maze4 Chipset = 8.6 LPM
Note: Alphacool has a new revision of the pump out ( Lang DDC-1 Plus) which again has an increased flow rate that once arrives will be tested in the same manner. (cheers Leeum)
Amendment 25/01/06
Laing DDC-1Plus With Alphacool Plexi Top ½” Barbs (side mount inlet & outlet)
Laing DDC-1Plus = 9.7 LPM
Laing DDC-1Plus + TDX (nozzle1) = 8.4 LPM
Laing DDC-1Plus With Alphacool Plexi Top ½” Barbs (top mount inlet - side mount outlet)
Laing DDC-1Plus = 14.5 LPM
Laing DDC-1Plus + TDX (nozzle1) = 10.5 LPM
Added 29/01/06
Laing DDC-1Plus With Alphacool Plexi Top ½” Barbs (top mount inlet - side mount outlet)
Laing DDC-1Plus + NV-78 = 11.5 LPM
Laing DDC-1Plus + NV-78 + TDX (nozzle1) = 9.2 LPM
Laing DDC-1Plus + Alphacool NVXP-3 6800/7800 = 6.9 LPM
Laing DDC-1Plus + Alphacool NVXP-3 6800/7800 + TDX (nozzle1) = 6.9 LPM
Laing D5
Laing D5 (set @ no 5) = 16.4 LPM
Laing D5 (set @ no 1) = 4.4 LPM