HSBC fell HK$3, or 2.7 per cent, to $108 yesterday after Morgan Stanley Dean Witter became the latest brokerage to voice concern over the stock's stellar performance in the past few months. Morgan Stanley downgraded HSBC to neutral from outperform, citing concerns in the bank's United States and British operations, which make up 65 per cent of its total asset base. The stock was trading at 'unprecedented' premiums to competitors across the globe, said Morgan Stanley's Amit Rajpal. 'From the perspective of an Asian-based investor, we foresee risk to . . . HSBC's overall balance sheet and earnings [in Europe and the US],' he said. 'We prefer purer-play Asian banks - our choice is Hang Seng Bank in Hong Kong.'