May 1, 2005- When asked about the best time to buy real estate, property mogul Donald Trump once remarked, "Real estate is always good as far as I'm concerned." Many investors agree, as record numbers of them are scooping up shares in publicly traded real estate investment trusts, or REITs, despite soaring valuations. So far they haven't been disappointed. REITs have outperformed almost every other investment class for five years running. But many experts believe that could soon change.