Funny. Looks like the old 4200 and gransport are the natural competitors for the vantage. I also feel that the older coupes age very well looks-wise. The older car will still be beautiful 15 years from now whereas I have not taken to the GT with its Japanese lookiing headlights and somewhat incoherent shape.
From driving both cars (albeit still limited time behind the wheel of the GT) the Aston is not a very good comparison car. Granted I'm not a big fan of the Aston - lots of curb appeal, but I don't think it's much deeper than that. The GT is clearly in a different class.
I also think its entertaining how quickly they forget about their own testing of the QP and its performance numbers on their test track. Oh well.
Jan 08 issue of car has a review of the Alfa 8C, which is a good read.