Automatic vs Quartz Watches: Differences and Which to Choose

Casio G-Shock GA-2100 or Daniel Wellington Classic 40mm: the short answer

If you don’t want to read the whole comparison: the Casio G-Shock GA-2100 is the default choice and the one we recommend to most people, whilst the Daniel Wellington Classic 40mm comes out on top in one specific scenario — when your priority is everyday wear. The real difference between the two isn’t in the specs; it’s in how they perform in the way you’ll actually be using them. We’ve broken it down point by point below.

Luminescence: Super-LumiNova and LumiBrite

Modern luminescent paint is not radioactive: it is a phosphorescent material that absorbs light and gradually releases it. Super-LumiNova (Switzerland) and LumiBrite (Seiko) are the models, with variants such as the bluish BGW9 or the greenish C3, which is the one that shines the brightest. What makes the difference in practice is not the paint brand but the layer thickness: that’s why a €150 Seiko can outshine a €1,500 Swiss watch. With diving watches, check that the bezel at 12 o’clock and the minute hand – which is the one that counts underwater – are also luminescent.

How to buy a watch without being ripped off

Four things to check before paying: that the salesperson whether it is the manufacturer or an authorised distributor (on marketplaces, check who is shipping the item and who is invoicing); that the warranty is the brand’s official one and not just the seller’s; that the specifications advertised match the official profile from the manufacturer, particularly crystal and ATM models, as these are where claims are most often exaggerated; and ensure the price isn’t significantly below market value, which is a common sign of a replica. Keep the box, paperwork and receipt: with watches, these add to the value should you ever sell it.

Glass: sapphire, mineral or acrylic

The sapphire is hard 9 on the Mohs scale: Only a diamond or materials containing corundum can scratch it, which is why it’s the best choice if you’re using the watch every day. The mineral (hardness 5–6) can be scratched by sand, keys or cement, although it withstands a single impact better without chipping. The Hardlex Seiko’s is a hardened mineral, somewhere in between. The acrylic It gets scratched just by looking at it, but you can polish it at home with polish in two minutes, giving it that warm, domed look of vintage watches. An anti-reflective coating on the inside makes the dial much easier to read than one on the outside, which wears off.

Solar and Eco-Drive: the maintenance-free option

If you don’t want to change the batteries or set the time, solar technology is the most practical solution on the market. The Eco-Drive Citizen charges a cell using any light, including artificial light, and stores energy to 6 months in total darkness; the Seiko equivalent is the Solar, and its Kinetic generates electricity from movement. The Spring Drive The Grand Seiko is a hybrid watch with a perfectly smooth seconds hand and quartz-level accuracy. The solar cell lasts between 10 and 20 years – far longer than the batteries it replaces – and the capacitor is replaceable.

• Quality of materials and finishes
• Recent verified reviews (including 3–4-star reviews)
• Warranty and returns policy
• Current price compared with its historical average
• Seller's reputation
• Make sure the key features suit your needs (day-to-day use)

Case size: the important figure is not the diameter

Everyone looks at the diameter in millimetres, but the person who decides whether a watch suits you is the lug to lug, the distance between the lugs. Rule of thumb: for a 16–17 cm wrist, look for a lug-to-lug measurement of just under 48 mm; up to 50–52 mm if your wrist is over 18 cm in diameter, 36–38 mm It is the classic style and the one that works best on a slender wrist or with a suit, 39–41 mm It’s the most versatile size available today, and anything over 44 mm takes you into the sports watch territory. A 40 mm watch with long, curved lugs looks better on the wrist than a 38 mm one with straight lugs.

Criterion	Casio G-Shock GA-2100Our choice	Daniel Wellington Classic 40mm
Ideal for	Balanced and general use	Day-to-Day Life
Strength	Value for money	Specific features
Reviews	Very positive and numerous	Positive
Approximate price	from around €320	from around €200
Recommendation	Our choice	Best alternative
View on Amazon	See price →	See price →

Straps and bracelets: the most cost-effective change

Changing the strap transforms a watch for €20–40 and is the best value-for-money upgrade there is. Measure the width between antlers (18, 20 and 22 mm are the most common) and choose according to your needs: steel for everyday use, skin for washing (never with water), rubber or FKM for sport and summer, and NATO made of nylon for a military look and quick changes. Look for pins made of quick release (quick-release) so that no tools are required. With steel bracelets, the detail that sets the good ones apart from the mediocre ones is the micro-adjustable fastening, which allows you to fine-tune the fit when your wrist swells in the heat.

Verdict: which one to choose

The Casio G-Shock GA-2100 for most people; the Daniel Wellington Classic 40mm if you’ll mainly be wearing it for everyday use. Neither is a bad buy; they’re just designed for different purposes: the mistake would be to choose based on the price on a particular day rather than on how you’ll actually use it over the coming years. Check the current price of both before making your final decision.

Frequently Asked Questions

Does a watch lose its value over time?

Almost all of them, yes – just like any consumer product: for most, you’ll get half the price or less when selling them second-hand. Only a handful of highly sought-after models hold their value or even increase in price. Buy the watch because you enjoy wearing it, not as an investment.

What size watch suits me best?

Focus on the lug-to-lug measurement rather than the diameter: under 48 mm for wrists measuring 16–17 cm, up to 52 mm if your wrist is over 18 cm. In terms of diameter, 39–41 mm is the most versatile range, whilst 36–38 mm is the classic choice for a slender wrist or a suit.

What width of strap do I need?

Check the distance between the lugs: 18, 20 and 22 mm will fit most watches. If your watch allows it, look for quick-release pins so you can change the strap without tools.

Can I go for a swim in the sea whilst wearing a diving watch?

Yes: a watch rated to 20 ATM and certified to ISO 6425 is designed for just that. Rinse it with fresh water when you come out of the water, as the salt crystallises on the crown and bezel and eventually corrodes the gaskets. And always check that the crown is screwed down before going into the water.

Why does my automatic watch stop working on my wrist?

Because you’re not winding it enough: the rotor needs to be active, and in an office environment, many watches don’t wind themselves fully. Give the crown 20–30 turns in the morning if the model allows for manual winding. If it stops even when worn all day, the problem lies with the movement and it needs servicing.

Should I go for the Casio G-Shock GA-2100 or the Daniel Wellington Classic 40mm?

The Casio G-Shock GA-2100 is the most well-rounded option and our default recommendation. The Daniel Wellington Classic 40mm makes sense if your priority is everyday wear. As a budget guide, the useful price range starts at around €200, and the best value is usually found at around €320.

By the Watch Guide Team · reviewed by

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