If your holding period spans decades, you need to be pretty particular about the stocks you buy. Which is exactly why you'll want to take a look at technology giant Alphabet Inc. (GOOG 0.51%), robotic surgery leader Intuitive Surgical, Inc. (ISRG -2.25%), and General Mills, Inc. (GIS -0.21%), a longtime leader in the packaged food space. Alphabet and Intuitive are plays on growing, high-tech businesses, while General Mills is a high-yielding necessity business that can pay you well to stick around over the years. If you take the time to research this trio, at least one of these three stocks should be enticing to you.

Mining the most valuable commodity in the world

Brian Stoffel (Alphabet Inc.): If you hear me talking about mining, you might think of copper, gold, or even (gasp) crypto-currencies. But they are all eclipsed by what I think is the most valuable commodity in the world right now: data. And no one has more data than Alphabet, parent company to Google.

Consider that earlier this year, Google Drive became the company's eighth product with over one billion users worldwide. It joined Search, GMaps, GMail, Android, Chrome, YouTube, and Google Play Store in that exclusive club. Almost all of these services are free to use -- largely because they offer the company gobs of data. Alphabet can then take that data and offer targeted ads with precision. 

A woman drawing a graph comparing risk and reward

Image source: Getty Images.

I wouldn't be surprised if there are eight more tools that will join this club over the next quarter century. Such a roster produces tons of cash. Over the past 12 months, Alphabet brought in $23 billion in free cash flow. It's currently sitting on a net cash (and investments) pile of over $100 billion. That's important, because it will help fund the company's moonshot projects -- like self-driving division Waymo

Best of all, while the company is firing on all cylinders, shares have fallen 15% from their 2018 highs. That means you can grab shares for 31 times trailing free cash flow. While that might not sound cheap, the company upped its capital spending markedly this year. I think in 2043, Alphabet will be a multitrillion-dollar company -- and you'll be glad to own shares.

The future of surgery

Keith Speights (Intuitive Surgical, Inc.): It wasn't all that long ago that the idea of using robots in performing surgeries would have been considered science fiction. But Intuitive Surgical changed things with its 1999 launch of the da Vinci robotic surgical system. I suspect that 50 years from now, the idea of not using robots in surgeries will be viewed as ancient history. 

Why is the future of surgery destined to include robotic systems? Variability of outcomes with current surgical procedures remains a significant problem. Studies have found that the bottom quartile of surgeons has three times more complications than the top quartile of surgeons. Intuitive Surgical's da Vinci system helps reduce that variability. 

There are plenty of opportunities for Intuitive Surgical to grow. Last year, around 877,000 surgeries across the world were performed using da Vinci. But more than 20 million invasive surgical procedures in total are performed each year in the U.S. alone. The unstoppable long-term trend of aging populations across the world will boost these numbers even higher. 

Intuitive Surgical will likely see increased competition. But the overall market growth should easily allow multiple companies to succeed. Also, Intuitive's large install base and strong track record give it a first-mover advantage that will be difficult to overcome.  

Adjusting with the times, again

Reuben Gregg Brewer (General Mills, Inc.): Packaged-food giant General Mills is in the doghouse. In fact, its 4.3% yield is higher than it was during the deep 2007-2009 recession. There are good reasons for that, including rising costs, shifting customer tastes, and a large, debt-funded acquisition. But don't get too caught up in the negatives, here.

Rising costs will be dealt with by cutting costs or raising prices. It may take a little time, but this is a normal part of the packaged-food business. Shifting customer tastes is a more difficult challenge because it means rejiggering the product portfolio. That said, the over 100-year-old company has done this before, too. It has added on-target brands like Annie's, Larabar, and Blue Buffalo pet food. Meanwhile, it is launching new versions of existing products, including extensions in its Yoplait yogurt division. History suggests it will figure this out, even if the process is bumpy.

GIS Dividend Yield (TTM) Chart

GIS Dividend Yield (TTM) data by YCharts.

Leverage, meanwhile, is indeed elevated. But when you step back, the fix required isn't all that extensive. For example, the Blue Buffalo acquisition pushed long-term debt from 60% of the capital structure to 67%. That's not that big a change. Meanwhile, General Mills sells necessity items, and its business tends to be pretty stable over time. It can shoulder the added debt burden, noting that it covered interest expenses 4.5 times over in the most recent quarter. 

There are warts here, but General Mills should be able to adjust, making now a pretty good time to consider buying this iconic food maker, and after losing a third of its value since mid-2016, the downside risk seems priced in already.