ESP vs AEIS vs MKSI vs DRS

For growth investors, Advanced Energy Industries, Inc.

(AEIS) is the stronger pick with 21. 4% revenue growth year-over-year, versus 9. 6% for MKS Inc. (MKSI). Espey Mfg. & Electronics Corp. (ESP) offers the better valuation at 20. 2x trailing P/E (16. 2x forward), making it the more compelling value choice. Analysts rate Advanced Energy Industries, Inc. (AEIS) a "Buy" — based on 24 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, Espey Mfg.

& Electronics Corp. (ESP) is the cheapest at 20. 2x versus Advanced Energy Industries, Inc. at 97. 0x. On forward P/E, Espey Mfg. & Electronics Corp. is actually cheaper at 16. 2x. The PEG ratio (P/E divided by earnings growth rate) is the most growth-adjusted single valuation metric: Espey Mfg. & Electronics Corp. wins at 0. 37x versus Advanced Energy Industries, Inc. 's 21. 35x — a PEG below 1. 0 traditionally signals the market is underpricing earnings growth.

Over the past 5 years, Espey Mfg.

& Electronics Corp. (ESP) delivered a total return of +333. 5%, compared to +143. 9% for MKS Inc. (MKSI). Over 10 years, the gap is even starker: DRS returned +36. 6% versus ESP's +167. 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), Espey Mfg.

& Electronics Corp. (ESP) is the lower-risk stock at 0. 74β versus MKS Inc. 's 2. 53β — meaning MKSI is approximately 243% more volatile than ESP relative to the S&P 500. On balance sheet safety, Leonardo DRS, Inc. (DRS) carries a lower debt/equity ratio of 17% versus 173% for MKS Inc. — giving it more financial flexibility in a downturn.

By revenue growth (latest reported year), Advanced Energy Industries, Inc.

(AEIS) is pulling ahead at 21. 4% versus 9. 6% for MKS Inc. (MKSI). On earnings-per-share growth, the picture is similar: Advanced Energy Industries, Inc. grew EPS 168. 5% year-over-year, compared to 28. 7% for Leonardo DRS, Inc.. Over a 3-year CAGR, ESP leads at 11. 0% 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.

Espey Mfg.

& Electronics Corp. (ESP) is the more profitable company, earning 18. 5% net margin versus 7. 5% for MKS Inc. — meaning it keeps 18. 5% of every revenue dollar as bottom-line profit. Operating margin tells a similar story: ESP leads at 18. 5% versus 9. 5% for DRS. At the gross margin level — before operating expenses — MKSI leads at 40. 4%, 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, Espey Mfg. & Electronics Corp. (ESP) is the more undervalued stock at a PEG of 0. 37x versus Advanced Energy Industries, Inc. 's 21. 35x. A PEG below 1. 0 is traditionally considered the threshold for growth-adjusted undervaluation. On forward earnings alone, Espey Mfg. & Electronics Corp. (ESP) trades at 16. 2x forward P/E versus 40. 0x for Advanced Energy Industries, Inc. — 23. 8x cheaper on a one-year earnings basis. Analyst consensus price targets imply the most upside for DRS: 15. 7% to $53. 33.

All stocks in this comparison pay dividends.

Espey Mfg. & Electronics Corp. (ESP) offers the highest yield at 1. 6%, versus 0. 1% for Advanced Energy Industries, Inc. (AEIS).

For long-horizon retirement investors, Espey Mfg.

& Electronics Corp. (ESP) is the stronger choice — it scores higher on the combination of lower volatility, dividend reliability, and long-term compounding (low volatility (β 0. 74), 1. 6% yield, +167. 4% 10Y return). Advanced Energy Industries, Inc. (AEIS) carries a higher beta of 2. 38 — meaning larger drawdowns in market downturns, which matters significantly when you cannot wait years for a recovery. Both have compounded well over 10 years (ESP: +167. 4%, AEIS: +880. 6%), 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 (ESP (Industrials) and AEIS (Industrials) and MKSI (Technology) and DRS (Industrials)), which means they face different economic cycles, regulatory environments, and macro sensitivities — making direct comparison nuanced.

In terms of investment character: ESP is a small-cap quality compounder stock; AEIS is a mid-cap high-growth stock; MKSI is a mid-cap quality compounder stock; DRS is a mid-cap quality compounder stock. ESP, DRS pay a dividend while AEIS, MKSI 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.