Difference between 120.2 and 120.3

How much performance difference would there be between the Thermochill 120.2 and 120.3? Enough for a £35 price difference? (I can get the 120.2 2nd hand)
Cooling CPU (Venice) GPU (Ultra) and Chipset. High flow pump

EDIT: Another quick question, are Ramsinks neccessary if watercooling. Using a Maze 4.

ramsinks will be nessesary if you are overclocking the ram of the card as the maze4 just covers the gpu core.

About .09 C/W or so according to BillA's calc's. To estimate the actual difference in Celsius, you'd need to know the heatload on the system and fans used. At 100W actual heat load, the 120.3 would cool by .9C better in theory, but again depends on fannage used.. at 200W, 1.8C, at 300w 2.7C and so on.

Ram sinks would be optional, and only will be needed when overclocking, Look at the stock cooler that it comes in it only covers one side of ram on the video card

Well its cooling overclocked 3200+ Venice, overclocked to Ultra 6800GT, and DFI NF4 Chipset when the block for it comes out. Shouldnt be to much of a difference, which I am glad of since I went for it £35 shipped with a shroud aint half bad.

Ramsinks seem to cost way to much over here, need to get some second hand.