Mid-cap stocks often strike the right balance between having proven business models and market opportunities that can support $100 billion corporations. However, they face intense competition from scaled industry giants and can be disrupted by new innovative players vying for a slice of the pie.

These dynamics can rattle even the most seasoned professionals, which is why we started StockStory - to help you separate the good companies from the bad. That said, here are two mid-cap stocks with huge upside potential and one best left ignored.

One Mid-Cap Stock to Sell:

First Solar (FSLR)

Market Cap: $20.93 billion

Headquartered in Arizona, First Solar (NASDAQ: FSLR) specializes in manufacturing solar panels and providing photovoltaic solar energy solutions.

Why Does FSLR Give Us Pause?

1. Annual revenue growth of 6.8% over the last five years was below our standards for the industrials sector
2. Investments to defend its competitive moat have ramped up over the last five years as its free cash flow margin decreased by 18.9 percentage points
3. Short cash runway increases the probability of a capital raise that dilutes existing shareholders

First Solar is trading at $195.34 per share, or 9.9x forward P/E. Dive into our free research report to see why there are better opportunities than FSLR.

Two Mid-Cap Stocks to Buy:

Insulet (PODD)

Market Cap: $23.93 billion

Revolutionizing diabetes care with its tubeless "Pod" technology, Insulet (NASDAQ: PODD) develops and manufactures innovative insulin delivery systems for people with diabetes, primarily through its Omnipod product line.

Why Will PODD Outperform?

1. Constant currency growth averaged 26.4% over the past two years, showing it can expand globally regardless of the macroeconomic environment
2. Free cash flow margin expanded by 25.4 percentage points over the last five years, providing additional flexibility for investments and share buybacks/dividends
3. Returns on capital are climbing as management makes more lucrative bets

Insulet’s stock price of $335 implies a valuation ratio of 71.6x forward P/E. Is now the right time to buy? See for yourself in our in-depth research report, it’s free.

SEI Investments (SEIC)

Market Cap: $10.91 billion

Founded in 1968 as Simulated Environments Inc. to train bank loan officers using computer simulations, SEI Investments (NASDAQ: SEIC) provides technology platforms, investment management, and operational solutions for financial institutions, wealth managers, and investors.

Why Should You Buy SEIC?

1. Products and services resonate with customers, evidenced by its respectable 8.1% annualized sales growth over the last two years
2. Performance over the past two years was turbocharged by share buybacks, which enabled its earnings per share to grow faster than its revenue
3. Market-beating return on equity illustrates that management has a knack for investing in profitable ventures

At $87.01 per share, SEI Investments trades at 17x forward P/E. Is now the time to initiate a position? Find out in our full research report, it’s free.

Stocks We Like Even More

Donald Trump’s April 2025 "Liberation Day" tariffs sent markets into a tailspin, but stocks have since rebounded strongly, proving that knee-jerk reactions often create the best buying opportunities.

The smart money is already positioning for the next leg up. Don’t miss out on the recovery - check out our Top 5 Growth Stocks for this month. This is a curated list of our High Quality stocks that have generated a market-beating return of 183% over the last five years (as of March 31st 2025).

Stocks that made our list in 2020 include now familiar names such as Nvidia (+1,545% between March 2020 and March 2025) as well as under-the-radar businesses like the once-small-cap company Comfort Systems (+782% five-year return). Find your next big winner with StockStory today for free. Find your next big winner with StockStory today. Find your next big winner with StockStory today

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