The 4200# number is largely regarded as fake news, but we'll see. I think it will be hard to get the weight up that high. With the GT350 around 3700lbs, its hard to imagine adding 500 lbs. I believe I read the DCT didnt add any weight.I am reading 4200 lbs on a couple different sites.
The 720 HP number was on that same "leaked" spec sheet as the 4200 lbs. When it was "leaked" last year, there were some lengthy articles about why the document was a fake.