Panmure Gordon has kept its 'buy' rating and 1,500p target price for easyJet after a strong pre-close trading update from the budget airline on Thursday morning.The broker said that the statement "suggests that the commercial and operational performance has continued to be robust across the network".easyJet revised its profit before tax (PBT) guidance for the full year to £470-480m, compared with the previous guidance of £450-480m. Meanwhile, revenue-per-seat growth at constant currency for the final quarter (three months to September 30th) is targeted at 6%, driven by strong demand in July and August."We believe that the long-term prospects for this business remain exciting. The company has a strong structural cost advantage over most of its competitors, creating a highly attractive value proposition," said analyst Gert Zonneveld."We expect seat revenues to rise in the coming years, primarily driven by modest capacity growth, maturing routes and bases, a growing proportion of business passengers and a more rigorous route management (driven by returns on capital employed). Costs (excluding fuel) appear to be under control," Zonneveld said.The stock was fluctuating between gains and losses on Thursday morning, trading down 0.3% at 1,310p by 10:55.BC