Former hedge-fund manager, author and philanthropist Whitney Tilson shares thoughts on Apple, Tesla and Warren Buffett with TheStreet's Brian Sozzi.

Tilson, a Berkshire Hathaway  (BRK.A - Get Report) (BRK.B - Get Report) expert, tells TheStreet we shouldn't count on Buffett retiring anytime soon. He says the legendary investor may stay at the helm of Berkshire for at least five more years. He would be 92 by then.

Tilson also speculates on Buffett's plans for his position in tech giant Apple (AAPL - Get Report) .

"He clearly views it as a long-term hold, and it will certainly compound over $1 trillion in the not too distant future -- and then double again in the next five years," says former hedge fund manager and Buffett expert Whitney Tilson. "I don't think it's a bad bet, as a Berkshire shareholder I am happy he owns Apple."

Elsewhere in the market, the erratic behavior of Tesla's Elon Musk is becoming a liability for the company, Tilson says. Tilson got caught on the wrong side of the trade in shorting Tesla (TSLA - Get Report) a few years back. But he warns that the time for the stock to go down a good bit is fast-approaching.

Watch and learn.

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