Vauxhall Astra H SRi 1.9 CDTI 150 with a dtuk tuning box on.
Take it you bought the box from Andrew Pawly? Heard some bad things about them boxes in the long run, they just overfuel your engine. Good fun while they last though. Only left mine on for a week a it was caining fuel and smoking like a bitch.
On the manual-DSG question the only thing I can say is test drive both, wish I had now as alot of people favour the DSG yet I keep thinking it will take some of the fun away from driving.
Im sure the 170 is tuneable to 200+ and will be alot more refined than the Astra, the Astra is a good car (looks wise) but I feel as if there was something missing and now in the GTI its all clear...build quality and refinement.
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