Some investors think they can bag the biggest returns by fishing at the shallow end of the stock pond, where the penny stocks swim. But while a move of just a few cents might net you a whopper, it's more likely to have you wading into the weeds of fraud and manipulation.

Instead, try casting your line to the other end of the price spectrum, among stocks that trade north of $100 a share. These three-digit stocks (and even four-, five-, and six-figure stocks) can have you telling tales of multibagger returns.

But regardless of how much it costs, it always comes down to whether the business is well-run. We'll check in with the smart set at Motley Fool CAPS to see which premium stocks they think smell a bit fishy and which ones they'd like to mount over the mantle.

High-priced honeys
One of the keys to the ascendancy of robotic-surgery specialist Intuitive Surgical (Nasdaq: ISRG), maker of the Da Vinci surgical system, has been its ability to generate revenue growth far in excess of what it spends on research and development. Intuitive's R&D has consistently accounted for about 8% of its revenue over the past few years, but it has enjoyed 29% compounded revenue growth over that same time period.

Yet some of Intuitive's peers enjoyed even better returns. MAKO Surgical (Nasdaq: MAKO), for example, spends about a quarter of its revenue on R&D while witnessing a 145% compound annual growth rate for sales. On the other side of the coin, Accuray (Nasdaq: ARAY) spends anywhere from 15% to 20% of its revenue on R&D for a mere 19% increase in sales. But whereas MAKO and Accuray are money-losing operations, Intuitive Surgical generates more than $0.28 in net profits for every dollar it takes in sales. That's getting some really good bang out of its R&D buck.

The point is that R&D is a key component of growing the business, and that type of innovation is at risk now that the Supreme Court has decided to uphold Obamacare as constitutional.

Part of the funding mechanism of the health-care law included a tax on medical-device makers. Yet it was not levied against their profits, but rather against their sales! By imposing a 2.3% tax on a device's sales price, it was estimated it would raise $29 billion over 10 years, but that money will come at the cost of jobs and R&D spending. Innovation has been put at risk and could be severely hampered in the future.

Analysts figure Intuitive Surgical can continue growing earnings at a 20% clip over the next five years, with 30% growth this year possible. I bought the stock in real life because I'm confident the tax will be retroactively eliminated or reduced in Congress, and innovation will be allowed to flourish, which plays to the surgical-robotics maker's strengths.

Let me know in the comments section below or on the Intuitive Surgical CAPS page if the pullback in its stock from recent highs represents an opportunity in light of the pending Supreme Court decision.

Buffett bummer
I'll admit it's been a long time since I've been enamored of Warren Buffett and Berkshire Hathaway (NYSE: BRK-B), though it has performed better than I gave either him or it credit for. I believed Buffett had lost some of his mojo, and I had an emotional response to his politics. But shares have risen 21% since he started for the first time ever buying back his own stock last September because he thought they were cheap. I'm still not bullish about Berkshire, though, because I'm doubtful in his successor's ability to replicate his wily investing acumen.

While I feel Buffett is an outlier, there are still plenty of professional investors who have a pretty good track record of their own, and buying into their businesses seems to make more sense. For me, Markel (NYSE: MKL) is the better bet here because of its CIO's own proven ability to pick winning investments, and because you're getting a stock often compared to Berkshire itself. The risk, of course, is that Berkshire represents the largest holding it has, so should that stock falter, so will Markel.

First-quarter results for the insurance conglomerate showed how it was able to bounce back from last year's reduced results. Per-share profits came in at $5.92, compared with $0.85 in the prior period, while the combined ratio shrank to 100% from 112% when it suffered losses related to a host of environmental disasters including the Australian floods, the New Zealand earthquake, and the Japanese earthquake and tsunami.

CAPS member Fudgethecat rides the ebb and flow of the insurance industry, enjoying how Markel "consistently outperforms other insurance companies despite the fact that it insures unusual risks such as pawn shops and vendor carts and homeowner associations."

I'm sure Buffett partisans have plenty to say about my diminished ardor for the Oracle, but tell me in the comments section if you also think Markel is the better play, and then add its stock to the Fool's personalized portfolio-tracking service to see whether the student can outperform the master.

If you are a Buffett minion, then you'll understand why he has bought banking stocks and why he'd buy one small bank in particular if he could. Get your copy of The Motley Fool's report "The Stocks Only the Smartest Investors Are Buying" today -- but hurry, as it won't be available forever.