i had the ITG previously, however given the choice next time, id choose the twintake, as from a guy on the seat forum who had both, he said the twintake was much better lower down the rpm band, whereas the ITG was better at th top. id prefer the midrange gain personally.
Dont disregard evoms either. alot of the higher powered TFSi's are running them.
i'd echo steves comment as well. standard car and intake =about 10Hp gain for £300-350. stage 1 remap will see 40-60hp gains (engine dependant) for £500. also an intake at stage 1 will give more like 20hp gains