Analyst Upgrades

• Polo Ralph Lauren (RL) to neutral from underperform at BofA/Merrill.
• Sigma-Aldrich (SIAL) to outperform from market perform at Leerink.
• Petrobras (PBR) to overweight from equal weight at Barclays.
• Silvercorp Metals (SVM) to buy from neutral at UBS.
• PROS (PRO) to buy from hold at Jefferies.
• Power Integrations (POWI) and Monolithic Power (MPWR) to buy from neutral at Roth Capital.
• Diodes (DIOD) to outperform from neutral at RW Baird.
• Whole Foods (WFMI) to hold from sell at Hapoalim.
• Sinclair Broadcast (SBGI) to overweight from neutral at JPMorgan.
• Sappi (SPP) to outperform from neutral at Macquarie.
• Alpha Natural (ANR) to buy from hold at BB&T.
• Watts Water (WTS) to buy from hold at Brean Murray.

For 25 years, Steven Halpern, editor of TheStockAdvisors.com, has surveyed the leading financial newsletter advisors asking for their favorite stocks for the coming year. This article is one of 100+ ideas in the Best Stocks for 2008 report.

"My favorite conservative idea for 2008 is Sigma-Aldrich (NASDAQ: SIAL), one of the world's largest providers of research chemicals, reagents, chromatography products, and related products," says Kelley Wright, editor of Investment Quality Trends.

"SIAL distributes more than 100,000 chemical products for use primarily in research and development, diagnosis of disease, and as specialty chemicals for manufacturing.

"The company believes it is the leader in the worldwide market for research chemicals, estimated at about $8.75 billion, with annual revenue growth of 3%-4%. The worldwide market for fine chemicals is estimated at $50 billion, with annual growth of 2%-3%. SIAL projects that it ranks among the top ten players in the fragmented fine chemical industry.

"The company's balance sheet is relatively strong, with a total debt-to-capital ratio of 26.6% as of September 30, 2007. This should allow SIAL to make additional acquisitions and further repurchases of its common stock. SIAL has acquired 83 million (adjusted) of its common shares since November 1999.