Thin, light and stylish, Sony's VAIO PCG-Z1SP, which will be available on 17 March, has all the designer chic that a fashion-conscious user could wish for. But beneath the surface gloss, does this 1.5GHz Pentium M/Centrino system deliver the goods in terms of performance and battery life? Our testing of this pre-production unit suggests that although performance is very good, you may need to buy the optional extended-life battery to put this system's mains-free longevity on a par with competing Pentium M/Centrino systems.