Would you be able to have a look at your long term fuel trims after you have done a few miles? AFAIK the ITG is the only full intake system I know which conforms to the OEM MAF diameter but I would like to now if the MAF housing not being oval has any ramifications.
The only intake which uses an oval MAF housing is the Carbonio but this is because it uses the OEM engine cover and MAF housing.
I ran the Carbonia pre-ITG, and whilst it ran OK in stage 1 spec, it just couldn't successfully deliver air supply at over 300bhp.
I don't have VAGCOM, so I will need to hook up with someone in the West Berkshire / South Oxfordshire area once I get back from holiday. I've only just got here o wont be back in the UK for a while. Apologies.