I find tht hard to believe. Have you sat in one? I'm not a little guy at 5 11 and 220, but I found there was plenty of room; the seat wasn't even all the way back. Way more room than the Gen II Viper.
Look for a test drive opportunity at a dealer in your area, drivers are coming to California in March.
I think you should try it...I'm 5' 11" and there is plenty of head and leg room left. The seat itself could easily go back another 4" so I think you'll be quite comfortable.
I finally got to sin in a Vantage today. I fit, just barely but I fit. Great looking car.
The 2007 models of the Vantage and DB9 have redesigned seats based on the Rapide concept car which accommodate...well...larger people. They are also lighter and feature improved head/thorax airbags and power folding for access to the rear.
I personally prefer the look of the current seat as do several other owners on other forums, but then I guess AML had some reason for making the change. More details on changes for the 2007 model year are available here: