Chris,
I realise that using an VATN turbo (I think I know who the manufacturer is now
) will be miles ahead of your standard off the shelf turbo. Kudos to the manufacturer, as that turbo removes the need for a wastegate and definitely reduces turbo lag (something most people complain about, but really wouldn't know what it is!) which is no worse than waiting for the secondaries to open.
As for the intercooler, check out Neuspeed's turbo kit for the A3 Golf, it auses and air to air with a hood scoop. I would prefer this to water to air, as air to air is far more efficient and LIGHTER, add a wter spray ONTO the intercooler as well as ducting and you are looking at a cheaper, lighter, less complex setup.
