Which is cheaper, the Formex Reef 42 mm or the Grand Seiko SBGR321?

At MSRP the Formex Reef 42 mm is the cheaper of the two at $2,414, against $5,200 for the Grand Seiko SBGR321 — a $2,786 gap before any retailer discounting.

Which is bigger, the Formex Reef 42 mm or the Grand Seiko SBGR321?

The Formex Reef 42 mm wears larger at 42mm versus 40mm for the Grand Seiko SBGR321 — a 2mm difference across the dial.

Which has better water resistance, the Formex Reef 42 mm or the Grand Seiko SBGR321?

The Formex Reef 42 mm is rated to 300m versus 100m for the Grand Seiko SBGR321.

Which has a longer power reserve, the Formex Reef 42 mm or the Grand Seiko SBGR321?

The Grand Seiko SBGR321 carries a 72-hour power reserve against 56 hours on the Formex Reef 42 mm.

What movement does the Formex Reef 42 mm run compared to the Grand Seiko SBGR321?

Both watches run automatic movements — the Formex Reef 42 mm uses the Sellita SW300-1 and the Grand Seiko SBGR321 uses the 9S65.

Side by side

Formex Reef 42 mmvsGrand Seiko SBGR321

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

Formex Reef 42 mm

reef-42mm-automatic-cosc-300m-black

MSRP $2,414

Grand Seiko SBGR321

sbgr321g

MSRP $5,200

At a glance

11 of 29 specs differ

Diameter

Reef 42 mm42mm

SBGR32140mm

Power Reserve

Reef 42 mm56h

SBGR32172h

Water Resistance

Reef 42 mm300m

SBGR321100m

MSRP

Reef 42 mm$2,414

SBGR321$5,200

Full specifications

Case

6 specs

Crystal & Dial

2 specs

AR Coating

Inner

Yes

Lume

Super-LumiNova

None

Movement

2 specs

Caliber

Sellita SW300-1

9S65

Power Reserve

56h

72h

Pricing

1 specs

MSRP

$2,414

$5,200

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What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Formex Reef 42 mm

The Formex Reef 42 mm is widely praised for its comfortable bracelet featuring a micro-adjust clasp, COSC-certified Sellita movement, and excellent build quality. Owners appreciate the gradient dial's visual appeal and the overall wearability. Some owners note the seconds hand does not perfectly align with markers, and one owner found the lugs' taper hinders third-party strap fit. The bracelet's length and sporty design are noted as limiting versatility by some. On balance, owners and reviewers rate the Formex Reef 42 mm highly for its impressive wearability and value at the price point.

Grand Seiko SBGR321 owners and reviewers widely praise its attractive design, compelling dimensions, and robust movement. The watch features sharp case lines with contrasting brushing and polishing, a 40mm steel case that provides presence without bulk, and 100m water resistance. Its sunburst blue dial, inspired by the dawn sky over Mount Iwate, showcases Grand Seiko's signature finishing on applied markers and hands, with a red-tipped seconds hand. The 9S65 automatic movement is noted for its precision, running within specifications, with one source reporting a +5 to -3 seconds a day rate and a 3-day power reserve. A blue rotor with a crimson rim, also inspired by Mount Iwate, is visible through the display caseback. On balance, owners and reviewers rate the Grand Seiko SBGR321 highly for its exceptional finishing and compelling blue dial design at its price point.

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