Here's why Alibaba is a winner: Pro

Alibaba's one red flag

The buzz is building for the initial public offering of Chinese e-commerce giant Alibaba, set to become the biggest IPO in U.S. history.

Sagework's Brian Hamilton is buying into that buzz, calling the company's 50 percent sales growth rate and 44 percent net profit margin "amazing."

"This company's got positive cash flow, net profits, good growth, big market," Hamilton said in an interview with CNBC's "Closing Bell."

"This is a winner at its current valuation."

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On Friday, Alibaba filed to sell up to $24.3 billion in stock and expects its stock to debut between $60 and $66 a share.

The company began its IPO road show in New York on Monday. Approximately 800 investors showed up at the Waldorf Astoria to hear founder Jack Ma and other executives make their case.

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One red flag with the IPO, Hamilton said, is the fact that buyers of Alibaba are buying the "regulatory environment of China, which is evolving and developing." However, he doesn't think it's a deal killer.

"The Chinese IPO market is a little bit volatile," he noted. "I would watch the value as the company goes public. That's the key. But a 44 percent net profit margin—holy crow."

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He's also watching the pre-IPO price.

"This is $160 billion valuation, so if the pre-IPO price goes way up, I would be a little bit more concerned."

—By CNBC's Michelle Fox. CNBC's Kayla Tausche contributed to this report.