its an old test so I searched on m5board.com and came up with this:

Conclusion: "Which of that three V10-sport cars is the best depends primary on three factors: the expected purpose of the car, the personal aspiraton, and – last but not least – the financial strength. If you are looking for a pure sport car, if you can do without a trunk and money is no object the Gallardo is best for you. The 4-wheel-drive Gallardo is not only the most exciting car in a formal view, but its dynamics is in line with its extrovert appearanceas well. If you, on the one hand, drive for long distances but, on the other hand, don't want to lose sight of the track and have a soft spot for most modern engine and transmission engineering than you can't miss out on the M6. The high consumption and the small 70l fuel tank prevent the M6 from being the *perfect* GT. The SRT-10 is a retro-classic with many sporty qualities but also with an obstinate and bulky character; it's an American 'primary rock'.