Head-to-Head Comparison

Casio Pro Trek PRG340-1 vs Mido Ocean Star GMT

Casio's timepiece meets Mido's diver

Quick Verdict

The Casio Pro Trek PRG340-1 ($150–$250) offers Tough Solar Quartz (No Battery Change) precision in the tier below the Mido Ocean Star GMT ($1,000–$1,500). The Pro Trek PRG340-1 measures 54.7 × 51.7 × 15.1mm and is rated 100m (10 ATM). The Ocean Star GMT counters with Swiss Made craftsmanship and 200m (20 ATM) water resistance. Both are exceptional watches for their respective tiers.

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Casio Pro Trek PRG340-1

Casio

Pro Trek PRG340-1

$150–$250

Mido Ocean Star GMT

Mido

Ocean Star GMT

$1,000–$1,500

Specifications Compared

FeatureCasio Pro Trek PRG340-1Mido Ocean Star GMT
Price$150–$250$1,000–$1,500
Case Size54.7 × 51.7 × 15.1mm44mm
MovementTough Solar (Solar Quartz)Automatic Caliber 80 (Base ETA C07.661)
Caliber TypeTough Solar Quartz (No Battery Change)Automatic (ETA C07.661 base)
Power ReserveTough Solar (Rechargeable)80 Hours
Water Resistance100m (10 ATM)200m (20 ATM)
CrystalMineral GlassSapphire with Double-sided AR
Case MaterialBio-Based ResinStainless Steel
OriginCasio (Japan)Swiss Made

Category-by-Category Analysis

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Design & Aesthetics

Edge: Draw

Casio's design language vs Mido's approach

The Casio Pro Trek PRG340-1 features a Bio-Based Resin case at 54.7 × 51.7 × 15.1mm with Mineral Glass protection. The Mido Ocean Star GMT offers Stainless Steel construction at 44mm with Sapphire with Double-sided AR. Both represent their brand's distinct design philosophy and heritage.

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Movement & Performance

Edge: Mido

Tough Solar (Solar Quartz) vs Automatic Caliber 80 (Base ETA C07.661)

The Pro Trek PRG340-1 runs the Tough Solar (Solar Quartz) (Tough Solar Quartz (No Battery Change), Tough Solar (Rechargeable) power reserve) at standard frequency. The Ocean Star GMT uses the Automatic Caliber 80 (Base ETA C07.661) (Automatic (ETA C07.661 base), 80 Hours reserve) at 21,600 vph (3 Hz). The Ocean Star GMT offers a longer power reserve.

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Wearability & Fit

Edge: Mido

54.7 × 51.7 × 15.1mm vs 44mm — different wrist presence

At 54.7 × 51.7 × 15.1mm, the Pro Trek PRG340-1 has a bolder wrist presence compared to the Ocean Star GMT at 44mm. Water resistance differs: 100m (10 ATM) vs 200m (20 ATM).

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Value & Cost of Ownership

Edge: Casio

Casio sits in the lower tier

The Casio Pro Trek PRG340-1 sits at $150–$250 and the Mido Ocean Star GMT at $1,000–$1,500. On the specs that outlast any price: the Pro Trek PRG340-1 uses Mineral Glass with Tough Solar (Rechargeable), against Sapphire with Double-sided AR and 80 Hours on the Ocean Star GMT. Service intervals are typically 5-7 years for both.

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Water Resistance

Edge: Mido

100m (10 ATM) vs 200m (20 ATM)

The Pro Trek PRG340-1 is rated to 100m (10 ATM) while the Ocean Star GMT handles 200m (20 ATM). The Ocean Star GMT offers superior water resistance.

Our Verdict

Casio

Pro Trek PRG340-1

Choose the Casio Pro Trek PRG340-1 if you prioritize Tough Solar Quartz (No Battery Change) engineering, Casio (Japan) craftsmanship, and 100m (10 ATM) water resistance. At $150–$250, it delivers Tough Solar (Solar Quartz) with Tough Solar (Rechargeable) power reserve.

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Mido

Ocean Star GMT

Choose the Mido Ocean Star GMT if you value Automatic (ETA C07.661 base) technology, Swiss Made heritage, and 44mm proportions. At $1,000–$1,500, the Automatic Caliber 80 (Base ETA C07.661) with 80 Hours power reserve makes it a compelling choice.

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The Bottom Line

The Casio Pro Trek PRG340-1 and Mido Ocean Star GMT represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Mido delivers Swiss Made engineering.

Frequently Asked Questions

Neither is objectively better — they serve different preferences. The Casio Pro Trek PRG340-1 ($150–$250) offers Tough Solar (Solar Quartz) with Tough Solar (Rechargeable) power reserve, while the Mido Ocean Star GMT ($1,000–$1,500) features Automatic Caliber 80 (Base ETA C07.661) with 200m (20 ATM) water resistance. Choose based on your priorities: Casio (Japan) craftsmanship vs Swiss Made engineering.
The Casio Pro Trek PRG340-1 offers better upfront value, sitting a tier lower at $150–$250. However, the Mido Ocean Star GMT may justify its premium with superior finishing, heritage, or resale value.
Both are suitable for daily wear. The Pro Trek PRG340-1 at 54.7 × 51.7 × 15.1mm with 100m (10 ATM) water resistance handles everyday situations. The Ocean Star GMT at 44mm with 200m (20 ATM) is similarly capable. The Pro Trek PRG340-1 uses Mineral Glass while the Ocean Star GMT uses Sapphire with Double-sided AR. Sapphire resists scratches noticeably better than mineral glass.

How This Page Was Made

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.