There’s no question that Netflix is currently the king of the over-the-top streaming-video providers, with a service that reaches more than 80 million users in over 200 countries, and hit shows that drive millions of those users to “binge-watch” entire seasons in a matter of days.

All this has put Netflix in an enviable spot, with enough cash to acquire whatever movie and TV projects it chooses to bid on, and a market cap in the $60 billion range—the same league as media and entertainment giants like 21st Century Fox and Time Warner. There has even been talk that Apple might want to acquire the company.

Count Morningstar Research as one of the skeptics. In a recent research report that took a look at the video-on-demand market, the investment management firm said that while Netflix is the clear winner in the space right now: “We have reservations about its ability to meet or exceed market expectations around future subscriber growth and margin expansion.”

The reasons for that skepticism include increasing competition from companies like Amazon (AMZN), which recently expanded its Prime Video offering to more than 200 countries, and has even deeper pockets that Netflix. It is expected to spend as much as $5 billion on content this year.

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In addition to the online retailing giant, there’s also Hulu—which is launching a “skinny bundle” cable-killer service soon—and a growing list of smaller providers such as CBS All Access (CBS).

Although the company has expanded internationally, Morningstar’s analysts say they see battles in the future with local content providers, and also a risk that demand runs head-first into a lack of broadband access in some of those developing markets.

In the U.S., Netflix has been able to compensate for some of the churn in its user base (from people unsubscribing) and the tightening of its margins by boosting its prices, including a recent “un-grandfathering” exercise that removed some of the early discounts that users got.

Morningstar, however, believes that U.S. consumers “have greater price sensitivity than previously expected,” and that this could serve to cap Netflix’s ability to raise prices and combat churn.

Competition from Amazon, Hulu, and others could lead to Netflix having to pay higher prices for the content it wants, which could also impact margins, the research firm says. Movie festivals like Sundance have already turned into a kind of bidding war between Netflix and Amazon.

The streaming giant has also expanded into new content areas, including comedy and “unscripted” or reality TV shows, both into which Netflix has been pouring money. But each foray into a new area also brings the risk that the content isn’t going to generate the returns Netflix requires.

Bottom line: Morningstar believes Netflix has a “fair market value” of just $73 a share. Because the stock is currently trading for $140 a share, that means a potential decline of almost 50% in value if it were to return to what Morningstar thinks is a fair price. It hasn’t been that low since 2015.

Instead of investing in Netflix, the research firm argues that investors who want exposure to the streaming-video market should be buying some of the traditional content companies instead, including 21st Century Fox (FOX) and Disney (DIS). These companies have a wider “moat” protecting them from competitors than Netflix does, the company says.

Although Netflix will likely continue to be one of the industry’s strongest players, Morningstar says, its valuation is stretched to the breaking point based on some of the risks and challenges the company is going to face over the coming months.

Mathew Ingram

Netflix Is Winning the Streaming Race—But for How Long?