Well I can ask you this: Where did they get their Diablo GT? From the factory? If it's privately owned, or if it's from a dealer, their not entirely free to do with the car as they please. Top speed can be at 7500 rpm, but you can be at 7500 rpm in 1st gear, and there's no harm done. The owners won't tell any difference. Infact pushing the engine is good for Lamborghini's because that's how Lamborghini engines are. If your dealing with the skidpad, pushing it to the limit means HARMING the car, as in burning the tires, etc., which is not good for the car. The owners will not be too happy about that. I'll give you a test for the Diablo 6.0 from R&T themselves: 0-60 mph: 3.6 seconds 1/4 mile: 12.0 seconds 0.99 g on the skid-pad. the 0.2 second difference between R&T and Motor Trend is due to the fact that R&T uses a different (slower) timing of the clutch. It seems like they did an Ok job with their 6.0, so it's possible that they got it from the factory. But if the Diablo 6.0 does 0.99 g, then it really does not make sense for the Diablo GT to do only 0.97 g tested by the same magazine, unless it was privately owned or from a dealer, so that they were restricted. R&T did not make the comparison between the Diablo GT and the Z06, so it's not safe to do so yourself. R&T got more g's and a higher slalom speed from their 360 Modena than their F50 on two unrelated tests. Even though it's the same magazine that tested them both, that's not a good representation of the relation between those two cars. The F50 has much better handeling than the 360 Modena, and there is no question about that, even though R&T's tests point to otherwise. In the same way, you can't compare the two unrelated tests of the Z06 and Diablo GT because you won't always come to the right conclusions. I could make a good case that the Modena handels better than the F50 based on R&T tests alone, but it's just not true. Regarding the '99 Diablo SV, Quatroroute has much easier access to the Lamborghini Factory than any American magazine, and they have the only test that I know of the '99 Diablo SV that's worth something. If your still looking for proof, the '98 and '99 Diablo SV is faster than the 6.0 beyond 60 mph, everyone who has driven it says so, and it's also faster than the F50 beyond 60 mph, which does the 1/4 mile in 12.1 seconds. It's entirely logical for it to do 12.0 seconds, and that's exactly what it did. Now the '97/'96 SV is a not the same car because it does not have VVT. I'd like to see if there are ANY tracks where a Viper GTS has a better lap time than a '98 or '99 Diablo SV. I don't think you will find any. Even if there are any tracks where a Viper GTS beats a '97 or '96 SV would be interesting. If R&T lists skid-pad tests for the Diablo's as "n/a" it means exactly what it says: Nothing. Either a) they didn't test it, or b) they know they were restricted from pushing the car too far. Either way, it doesn't tell you anything about the car. Trust me, they are not trying to sheild Lamborghini from disgrace or something, if that is what you are hoping or thinking.