Tissot PRX Powermatic 80 vs Casio G-Shock GA-B2100 CasiOak
Tissot's timepiece meets Casio's diver
Quick Verdict
The Casio G-Shock GA-B2100 CasiOak (~$144) delivers Casio Quartz (Solar-Powered) technology at $706 less than the Tissot PRX Powermatic 80 (~$850). The PRX Powermatic 80 justifies its premium with Swiss Made heritage and Automatic Powermatic 80.111. Both represent excellent choices in the luxury watch category.
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Specifications Compared
| Feature | Tissot PRX Powermatic 80 | Casio G-Shock GA-B2100 CasiOak |
|---|---|---|
| Price | ~$850 | ~$144 |
| Case Size | 40mm | 44.4mm |
| Movement | Automatic Powermatic 80.111 | Quartz Module 5611 (Tough Solar + Bluetooth) |
| Caliber Type | In-House Automatic (ETA C07.111 base) | Casio Quartz (Solar-Powered) |
| Power Reserve | 80 Hours | — |
| Water Resistance | 100m (10 ATM) | 200m (20 ATM) |
| Crystal | Scratch-resistant Sapphire | Mineral Glass |
| Case Material | 316L Stainless Steel | Carbon Core Guard Resin |
| Origin | Swiss Made | Made in Japan |
Category-by-Category Analysis
Design & Aesthetics
Tissot's design language vs Casio's approach
Movement & Performance
Automatic Powermatic 80.111 vs Quartz Module 5611 (Tough Solar + Bluetooth)
Wearability & Fit
40mm vs 44.4mm — different wrist presence
Value & Cost of Ownership
Casio is $706 more affordable
Water Resistance
100m (10 ATM) vs 200m (20 ATM)
Materials Face-Off
| Component | Tissot PRX Powermatic 80 | Casio G-Shock GA-B2100 CasiOak |
|---|---|---|
| Case alloy | Stainless steel 316L (medical-grade, with composition Cr 16–18%, Ni 10–14%, Mo 2–3%) — the standard mid-range Swiss spec; not 904L (Rolex Oystersteel | Casio's proprietary monocoque case technology integrating carbon fibers into fine resin. The carbon fibers dramatically raise the tensile strength and modulus of elasticity of the case structure, allowing the GA-2100 to achieve an 11.8mm thickness — the thinnest analog G-Shock at launch — while maintaining full 10m drop impact resistance. Total case weight: 51g. |
| Sapphire crystal | Synthetic corundum (Al₂O₃) grown via the Verneuil process, Mohs hardness 9. Anti-reflective coating on the interior surface only (single-side AR is st Mohs 9 | Flat mineral glass with Mohs hardness ~6. Thermally tempered for impact resistance — flexes under force rather than shattering like sapphire. Not scratch-proof, but replacement crystals cost ~$10. |
| Lume specification | Super-LumiNova grade BGW9 (blue-green daylight tone, blue emission in some variants) or C3 (yellow-green) depending on dial colour family. Glow durati | Durable urethane polymer resistant to sweat, saltwater, UV radiation, and skin oils. Features quick-release spring bars. Known to last 5–10 years with daily wear before degradation. |
| Bracelet alloy | Stainless steel 316L matching the case. | Secured by 4 Phillips screws for 200m (20 ATM) water resistance. Houses two SR726W silver-oxide button cell batteries accessible for user replacement. |
| Premium Lineage: Cobarion® & DAT55G Titanium (MRG-B2100) | — | The luxury MRG-B2100 variant ($3,500+), hand-assembled at Yamagata Casio's Premium Production Line (PPL) by certified "Medalist" craftsmen, uses Cobarion® (cobalt-chromium alloy, 4× harder than pure titanium) bezels and DAT55G titanium (3× harder than pure titanium) bracelet links. |
Cost of Ownership Compared
The Casio G-Shock GA-B2100 CasiOak saves you $963 over 5 years of ownership
Who Should Pick Which
Pick the Tissot PRX Powermatic 80 if…
- Strong value proposition under $1,000 with automatic Swiss movement
- Active lifestyle wearers — 100m water resistance handles swimming and water sports
- Weekend warriors — 80-hour power reserve means it survives two days off the wrist
- Those who prioritize scratch resistance — sapphire crystal
- Integrated-bracelet aesthetic fans wanting the Royal Oak look for 1/20th the price
Pick the Casio G-Shock GA-B2100 CasiOak if…
- Anyone wanting an indestructible daily beater under $100 with serious design credibility
- Water sports enthusiasts — 200m WR with G-Shock shockproofing
- Watch modding enthusiasts — massive aftermarket ecosystem of metal conversion kits
- High-end collectors needing a dedicated beater alongside their luxury pieces
Tissot PRX Powermatic 80
- Retail markup is generous. The PRX commonly transacts at 30–40% under retail on Jomashop, Tissot's own e-commerce promotions, and authorized online dealers. Paying full $725 retail is rarely the right move — it usually means immediate ~30% loss the moment you walk out the door.
- Proprietary endlink limits strap options. The integrated bracelet design means you cannot easily put a NATO, leather two-piece, or rubber strap on the PRX without specialist hardware. This bothers some buyers more than they expect.
- Bracelet sizing is fiddly. Links are joined by screws (good — adjustable at home with a tool), but the screws are tiny and stripping them is common for inexperienced owners. Take it to a watchmaker for sizing if you're unsure.
- 3 Hz "slow" seconds. The reduced frequency (21,600 vph vs. 28,800 vph in some peer movements) means the seconds hand visibly sweeps at 6 ticks/second rather than 8. Some buyers expecting the smoother high-beat sweep find this a minor disappointment.
Casio G-Shock GA-B2100 CasiOak
- Stealth-black legibility deficit: The GA2100-1A1 has absolutely no Neobrite luminescent paint on hands or indices. Low-light readability is poor — you must rely entirely on the Double LED Super Illuminator.
- Mineral glass scratches: Not sapphire. Daily beater use will accumulate minor scuffs over time. Replacement crystals are cheap (~$10) but require caseback removal.
- Tiny digital subdisplay: The LCD window at 4:30 is small and genuinely difficult to read for anyone with less than perfect vision. The Hand-Shift feature (sweeps hands to 7:35 position to clear the LCD) helps but isn't a substitute for a full digital display.
- Module 5611 is quartz: For mechanical-watch purists, this is a non-starter. For everyone else, it's a feature — better accuracy (±15 sec/month), no winding, no expensive servicing, and 3-year battery life.
Our Verdict
Tissot
PRX Powermatic 80
Choose the Tissot PRX Powermatic 80 if you prioritize In-House Automatic (ETA C07.111 base) engineering, Swiss Made craftsmanship, and 100m (10 ATM) water resistance. At ~$850, it delivers Automatic Powermatic 80.111 with 80 Hours power reserve.
Check Price on AmazonCasio
G-Shock GA-B2100 CasiOak
Choose the Casio G-Shock GA-B2100 CasiOak if you value Casio Quartz (Solar-Powered) technology, Made in Japan heritage, and 44.4mm proportions. At ~$144, the Quartz Module 5611 (Tough Solar + Bluetooth) with ample power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Tissot PRX Powermatic 80 and Casio G-Shock GA-B2100 CasiOak represent two distinct approaches to fine watchmaking — the Tissot bringing Swiss Made tradition while Casio delivers Made in Japan engineering.