Would you tell Kate Moss to get a face lift and go on a diet? Probably not but when there are younger and thinner models coming through the ranks a makeover might be tempting. For two years the carbon fibre XP 500 has been the supermodel of lightweight ski mountaineering boots but next season it faces competition from the fresh faced Sportiva Stratos, Dynafit Dy.N.A. and Scarpa F1 Carbon.