Through the prism of The Good, the Bad and the Ugly on Wall Street, here's Warren Buffett off the cuff Thursday.

With the yield on the 10-year Treasury at around 2.42 percent Thursday, billionaire investor Warren Buffett told CNBC he's not going to "start salivating" over that kind of return.

Buffett said on "Squawk Box" that he'd take stocks over bonds because he knows he's going to do better.

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With less than four years left, Buffett has a commanding lead in a decade-long bet that put a low-fee stock index fund up against a portfolio of high-priced hedge funds. Buffett told CNBC Thursday: "I'm quite aways ahead on that bet now."

Buffett said he regrets his investment in U.K. supermarket operator Tesco. He'd lost over $700 million, as of last month, with Tesco shares down about 45 percent this year. "That was a huge mistake by me," he admitted.

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—CNBC's Jeff Morganteen contributed to this report.