GSM vs CSTM vs AMG vs MP vs MTRN

For growth investors, MP Materials Corp.

(MP) is the stronger pick with 35. 1% revenue growth year-over-year, versus -18. 8% for Ferroglobe PLC (GSM). Affiliated Managers Group, Inc. (AMG) offers the better valuation at 13. 1x trailing P/E (9. 0x forward), making it the more compelling value choice. Analysts rate Ferroglobe PLC (GSM) a "Buy" — based on 11 analyst ratings — the highest consensus in this comparison. The "better buy" depends entirely on your goals: growth investors should weight revenue trajectory, value investors should weight P/E and PEG, and income investors should weight dividend yield and streak.

On trailing P/E, Affiliated Managers Group, Inc.

(AMG) is the cheapest at 13. 1x versus Materion Corporation at 53. 4x. On forward P/E, Affiliated Managers Group, Inc. is actually cheaper at 9. 0x. The PEG ratio (P/E divided by earnings growth rate) is the most growth-adjusted single valuation metric: Affiliated Managers Group, Inc. wins at 0. 23x versus Materion Corporation's 0. 82x — a PEG below 1. 0 traditionally signals the market is underpricing earnings growth.

Over the past 5 years, Materion Corporation (MTRN) delivered a total return of +155.

6%, compared to -9. 0% for Ferroglobe PLC (GSM). Over 10 years, the gap is even starker: MTRN returned +724. 3% versus GSM's -54. 4%. Past returns do not guarantee future results, and the stock with the higher historical return may already have its best growth priced in.

By beta (market sensitivity over 5 years), Affiliated Managers Group, Inc.

(AMG) is the lower-risk stock at 1. 14β versus Constellium SE's 1. 85β — meaning CSTM is approximately 63% more volatile than AMG relative to the S&P 500. On balance sheet safety, Ferroglobe PLC (GSM) carries a lower debt/equity ratio of 42% versus 2% for Constellium SE — giving it more financial flexibility in a downturn.

By revenue growth (latest reported year), MP Materials Corp.

(MP) is pulling ahead at 35. 1% versus -18. 8% for Ferroglobe PLC (GSM). On earnings-per-share growth, the picture is similar: Materion Corporation grew EPS 1179% year-over-year, compared to -31. 3% for Ferroglobe PLC. Over a 3-year CAGR, MTRN leads at 0. 6% annualised revenue growth. Higher growth typically commands a higher valuation multiple — check whether the premium P/E or P/S is justified by the growth rate using the PEG ratio.

Affiliated Managers Group, Inc.

(AMG) is the more profitable company, earning 29. 3% net margin versus -31. 2% for MP Materials Corp. — meaning it keeps 29. 3% of every revenue dollar as bottom-line profit. Operating margin tells a similar story: AMG leads at 31. 8% versus -44. 6% for MP. At the gross margin level — before operating expenses — AMG leads at 86. 0%, reflecting greater pricing power or product mix advantage. Stronger margins indicate durable pricing power, lower cost of revenue, or higher mix of software/services. They are one of the clearest signs of business quality.

The PEG ratio (forward P/E divided by expected earnings growth rate) is the most precise measure of undervaluation relative to growth potential.

By this metric, Affiliated Managers Group, Inc. (AMG) is the more undervalued stock at a PEG of 0. 23x versus Materion Corporation's 0. 82x. A PEG below 1. 0 is traditionally considered the threshold for growth-adjusted undervaluation. On forward earnings alone, Affiliated Managers Group, Inc. (AMG) trades at 9. 0x forward P/E versus 274. 3x for MP Materials Corp. — 265. 3x cheaper on a one-year earnings basis. Analyst consensus price targets imply the most upside for MP: 13. 2% to $78. 25.

In this comparison, GSM (1.

4% yield), MTRN (0. 3% yield) pay a dividend. CSTM, AMG, MP do not pay a meaningful dividend and should not be held primarily for income.

For long-horizon retirement investors, Ferroglobe PLC (GSM) is the stronger choice — it scores higher on the combination of lower volatility, dividend reliability, and long-term compounding (1.

4% yield). Constellium SE (CSTM) carries a higher beta of 1. 85 — meaning larger drawdowns in market downturns, which matters significantly when you cannot wait years for a recovery. Both have compounded well over 10 years (GSM: -54. 4%, CSTM: +503. 1%), confirming both are viable long-term holds — but the lower-volatility option typically results in less emotional selling during corrections. Retirement portfolios generally favour predictability over maximum returns. Consult a financial advisor before making allocation decisions.

These companies operate in different sectors (GSM (Basic Materials) and CSTM (Basic Materials) and AMG (Financial Services) and MP (Basic Materials) and MTRN (Basic Materials)), which means they face different economic cycles, regulatory environments, and macro sensitivities — making direct comparison nuanced.

In terms of investment character: GSM is a small-cap quality compounder stock; CSTM is a small-cap high-growth stock; AMG is a small-cap high-growth stock; MP is a mid-cap high-growth stock; MTRN is a small-cap quality compounder stock. GSM pays a dividend while CSTM, AMG, MP, MTRN do not, making them suitable for different income and tax situations. These fundamental differences mean investors should not choose between them on a single metric — the "better stock" depends entirely on which of these characteristics aligns with your investment strategy.