The thing your forgetting is the handling makes a huge difference and then acceleration and then top speed look at the ascari a10 and the gumpert apollo fastest round the top gear test track but havn't got the highest top speed some American cars can handle well but not usually that is why i think the veyron is better but who is going to go 250mph you just can't do it in most places and if you get to that speed on public roads your probably going to crash and die.