Warren Buffett's success as an investor means that the portfolio of stocks within Berkshire Hathaway get a lot of attention. Although you always have to make your own buy-and-sell calls, there are a couple of interesting stocks inside Buffett's investment vehicle worth thinking about today. The list includes Chevron (CVX 1.89%), Coca-Cola (KO -1.04%), and American Express (AXP -3.15%). Here which ones are probably worth buying, and the one that you may want to avoid.

Chevron is falling behind -- and that's perfectly fine.

Chevron is one of the world's largest integrated energy companies. That means that its business spans the entire spectrum of the sector, from the upstream (oil and natural gas production) through the midstream (pipelines) and all the way to the downstream (chemicals and refining). This provides some balance to the company's financial results, since each segment of the industry performs in a slightly different way.

Ultimately, for an energy firm like Chevron, the fluctuations in its performance are less severe than they would be if it operated solely in the upstream sector. This stability positions it as a reliable option for long-term investors interested in the energy industry.

Helping things along is one of the strongest balance sheets in the sector, with a very low debt-to-equity ratio of 0.17x.

Currently, the primary draw is the dividend, which boasts a yield of 4.3%. This impressive yield is supported by a dividend that has seen annual increases for more than thirty years. However, it's worth noting that the average yield in the energy sector sits at approximately 3.3%, indicating that Chevron is currently lagging in stock performance.

Part of the situation stems from an acquisition that hasn't met expectations. Additionally, Chevron's disappointing performance is linked to the current low energy prices. Nevertheless, for those with a long-term investment perspective, this established player in the industry may be a solid buy right now. Earning a yield that surpasses the industry average while anticipating a rebound isn't a bad position to be in.

Coca-Cola has seen a decline in its appeal, making it an enticing opportunity for potential buyers.

Coca-Cola stands out as one of the most well-known brands globally, and its stock is typically considered quite pricey. However, a recent decline in price has made the shares more appealing, provided you're comfortable investing a reasonable amount for a top-tier company.

To provide some numbers, this Dividend King's dividend yield is about 3.2%. That's roughly middle of the road over the past decade, hinting at a reasonable price. Backing up that view are more traditional valuation metrics like price-to-sales and price-to-earnings, both of which are a little below their five-year averages. While it wouldn't be fair to suggest Coca-Cola is a screaming buy, it does look reasonably priced.

The real story, however, is what you are getting for that price. Coca-Cola's business sports robust margins, a healthy balance sheet, and a beverage brand portfolio that is second to none (thanks largely to its namesake soda). While investors might have some concerns about inflationary pressures, new weight loss drugs, and even increasing scrutiny of snack foods, given the long and successful history here, it seems highly likely that Coca-Cola remains an industry leader. And that suggests that the dividend will keep getting paid and continue to rise over time -- exactly what a conservative income investor wants to see.

American Express is a fantastic company, although it tends to be on the pricier side.

American Express operates as a payment processor that caters to affluent consumers. This is a strong market segment, as affluent individuals generally manage to navigate economic challenges with greater ease. In fact, the transaction fees that the company earns from processing payments are typically stable and consistent over time.

All in, American Express is an attractive business. But as Benjamin Graham, the man who helped to train Warren Buffett, said, a great company can be a bad investment if you pay too much for it.

After roughly doubling in price in about a year's time, American Express is starting to look expensive. The company's price-to-sales, price-to-earnings, price-to-cash flow, and price-to-book value ratios are all well above their five-year averages.

If you are a more active investor who cares about valuation, you might want to take some profits here. It would be understandable if long-term investors wanted to stick around, given the underlying business, but new investors should probably stay on the sidelines until there's a better entry point.

A touch of Buffett motivation

Even Warren Buffett, known as the Oracle of Omaha, isn't infallible. Therefore, it's wise to approach Berkshire Hathaway's portfolio with some skepticism. Additionally, it's important to keep in mind that Buffett typically adopts a buy-and-hold strategy, meaning that the assets currently in his portfolio may not necessarily align with what he would choose to invest in today.

If you're seeking investment suggestions, examining Buffett's current stock portfolio raises intriguing points regarding Chevron, Coca-Cola, and American Express. The first two appear to be solid buying opportunities, whereas the latter seems a tad overpriced at this moment.