Omega Speedmaster Professional vs Longines HydroConquest Automatic
Omega's chronograph meets Longines's diver
Quick Verdict
The Longines HydroConquest Automatic ($1,500–$2,500) delivers ETA-Based Automatic with Silicon Balance Spring technology in the tier below the Omega Speedmaster Professional ($5,000–$10,000). The HydroConquest Automatic measures 41mm and is rated 300m (30 ATM). The Speedmaster Professional justifies its premium with Swiss Made heritage and Manual-Winding Caliber 3861. Both represent excellent choices in the luxury watch category.
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Specifications Compared
| Feature | Omega Speedmaster Professional | Longines HydroConquest Automatic |
|---|---|---|
| Price | $5,000–$10,000 | $1,500–$2,500 |
| Case Size | 42mm | 41mm |
| Movement | Manual-Winding Caliber 3861 | Automatic L888.5 |
| Caliber Type | In-House Manual-Winding Manufacture (Co-Axial) | ETA-Based Automatic with Silicon Balance Spring |
| Power Reserve | 50 Hours | 72 Hours |
| Water Resistance | 50m (5 ATM) | 300m (30 ATM) |
| Crystal | Hesalite or Sapphire | Sapphire with Anti-Reflective Coating |
| Case Material | Stainless Steel | Stainless Steel |
| Origin | Swiss Made | Swiss Made |
Category-by-Category Analysis
Design & Aesthetics
Omega's design language vs Longines's approach
The Omega Speedmaster Professional features a Stainless Steel case at 42mm with Hesalite or Sapphire protection. The Longines HydroConquest Automatic offers Stainless Steel construction at 41mm with Sapphire with Anti-Reflective Coating. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Manual-Winding Caliber 3861 vs Automatic L888.5
The Speedmaster Professional runs the Manual-Winding Caliber 3861 (In-House Manual-Winding Manufacture (Co-Axial), 50 Hours power reserve) at 21,600 vph (3 Hz) frequency. The HydroConquest Automatic uses the Automatic L888.5 (ETA-Based Automatic with Silicon Balance Spring, 72 Hours reserve) at 25,200 vph (3.5 Hz). The HydroConquest Automatic offers a longer power reserve.
Wearability & Fit
42mm vs 41mm — different wrist presence
At 42mm, the Speedmaster Professional has a bolder wrist presence compared to the HydroConquest Automatic at 41mm. Water resistance differs: 50m (5 ATM) vs 300m (30 ATM).
Value & Cost of Ownership
Longines sits in the lower tier
The Omega Speedmaster Professional sits at $5,000–$10,000 and the Longines HydroConquest Automatic at $1,500–$2,500. On the specs that outlast any price: the Speedmaster Professional uses Hesalite or Sapphire with 50 Hours, against Sapphire with Anti-Reflective Coating and 72 Hours on the HydroConquest Automatic. Service intervals are typically 5-7 years for both.
Water Resistance
50m (5 ATM) vs 300m (30 ATM)
The Speedmaster Professional is rated to 50m (5 ATM) while the HydroConquest Automatic handles 300m (30 ATM). The HydroConquest Automatic offers superior water resistance.
Materials Face-Off
| Component | Omega Speedmaster Professional | Longines HydroConquest Automatic |
|---|---|---|
| Co-Axial Caliber 3861 | Manual-wind chronograph with Co-Axial escapement (George Daniels design, licensed 1999). Si14 silicon balance spring, free-sprung balance, 234 components, 26 jewels | Zirconium oxide (ZrO₂) with engraved and paint-filled 60-minute dive scale Mohs 8.5 |
| Hesalite Crystal | Hardened acrylic (Mohs ~2–3) with embossed central Omega logo — the NASA flight-qualified specification Mohs 2.5 | Flat sapphire with anti-reflective coating on the underside Mohs 9 |
| Silicon Balance Spring (Si14) | Omega's proprietary Si14 silicon hairspring — in series production since 2008 | Si hairspring in the L888.5 caliber — introduced 2020 across the HydroConquest line |
| Aluminum Tachymeter Bezel | Fixed black anodized aluminum with white tachymeter scale. Preserves the "DOT OVER NINETY" detail from the Apollo 11–era watches | Brushed flanks with polished bevel edges — mixed finishing for visual depth |
| Stainless Steel Case | 42mm asymmetric case with integrated crown guards (added in 1964 for the 105.012 — the reference Buzz Aldrin wore on the Moon) | Applied to sword-style hands and all hour indices |
Cost of Ownership Compared
The Longines HydroConquest Automatic saves you $5,567 over 5 years of ownership
Who Should Pick Which
Pick the Omega Speedmaster Professional if…
- History and heritage enthusiasts — the only watch worn on the Moon, with NASA documentation to prove it
- METAS Master Chronometer accuracy at sub-$8,000 — antimagnetic to 15,000 gauss, 0/+5 sec/day
- Chronograph lovers — the manual-wind ritual and hand-wound feel is deeply satisfying
- Value seekers at grey market $5,200–$5,500 — one of the cheapest 5-figure-quality chronographs from a top-tier maison
- Available off-the-shelf — walk into any Omega boutique and buy one today (no Rolex-style waitlist)
Pick the Longines HydroConquest Automatic if…
- Best-in-class 72-hour power reserve at sub-$2,000
- Silicon hairspring antimagnetic protection at an accessible price
- Swiss heritage enthusiasts — Longines' 1832 founding and Olympic/aviation history
- Legitimate 300m dive capability with everyday wearability
- Value seekers — at grey-market pricing the spec-per-dollar is nearly unbeatable
Omega Speedmaster Professional
- Hesalite scratches — acrylic at Mohs ~2–3 is dramatically softer than sapphire. Polishes out with PolyWatch in 5 minutes, but it's high-maintenance for desk-diving wear
- No screw-down crown, 50m water resistance — this is a NASA chronograph, not a dive watch. Shower-safe, swim-cautious, never deep water
- Manual wind — not for the set-and-forget buyer. Daily winding is part of the ritual; some find it charming, some find it inconvenient
- Wears thick at 13.18mm with a proud bezel — reads as 43–44mm visually because of the broad lug profile
Longines HydroConquest Automatic
- ETA-base movement at this price — excellent but not "in-house" in the purist sense
- 21mm lug width — awkward for aftermarket straps (most are 20mm or 22mm)
- 25,200 vph (3.5 Hz) — seconds hand sweep is less smooth than 28,800 vph competitors
- Not COSC-certified — no chronometer guarantee (unlike Tudor or Omega at similar prices)
Our Verdict
Omega
Speedmaster Professional
Choose the Omega Speedmaster Professional if you prioritize In-House Manual-Winding Manufacture (Co-Axial) engineering, Swiss Made craftsmanship, and 50m (5 ATM) water resistance. At $5,000–$10,000, it delivers Manual-Winding Caliber 3861 with 50 Hours power reserve.
Check Price on AmazonLongines
HydroConquest Automatic
Choose the Longines HydroConquest Automatic if you value ETA-Based Automatic with Silicon Balance Spring technology, Swiss Made heritage, and 41mm proportions. At $1,500–$2,500, the Automatic L888.5 with 72 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Omega Speedmaster Professional and Longines HydroConquest Automatic represent two distinct approaches to fine watchmaking — the Omega bringing Swiss Made tradition while Longines delivers Swiss Made engineering.
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Our comparisons are generated from a hand-maintained specification database and reviewed under our editorial standards. We use AI tools to assemble pages from that data. We don’t invent specs: every number traces back to the database, and when we correct an entry, the fix is applied site-wide. As an Amazon Associate, The Horologist earns from qualifying purchases.