Side by side

Formex Reef 42 mmvsSeiko Monster

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

Reef 42 mm
FormexReef 42 mm
MSRP $2,414
Monster
SeikoMonster
MSRP $550
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.

Seiko Monster

Owners widely praise the Seiko Prospex Sea for its excellent value, robust build, and superb lume, with many noting its comfortable wearability. Reviewers consistently highlight its impressive finishing and classic dive watch design, often comparing it favorably to older models. Some owners find the size substantial, with one noting it as big, thick, and heavy on a 6.5-inch wrist, while others find it perfect. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional value and robust, classic dive watch design.

At a glance

11 of 29 specs differ
Diameter
Reef 42 mm42mm
Monster42.4mm
Power Reserve
Reef 42 mm56h
Monster41h
Water Resistance
Reef 42 mm300m
Monster200m
MSRP
Reef 42 mm$2,414
Monster$550

Full specifications

Case

5 specs
Diameter
42mm
42.4mm
Thickness
11.4mm
13.4mm
Lug-to-Lug
47mm
49.4mm
Lug Width
22mm
20mm
Water Resistance
300m
200m

Crystal & Dial

2 specs
Crystal
Sapphire
Hardlex
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Sellita SW300-1
4R36
Power Reserve
56h
41h
Jewels
25
24

Pricing

1 specs
MSRP
$2,414
$550
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