Side by side

Formex Reef 42 mmvsSeiko 5KX

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

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 5KX

Owners widely praise the Seiko 5 Sports SKX series for its strong lume and comfortable wearability, with many noting its compact feel due to a short lug-to-lug length. The NH36 movement's accuracy varies, with typical performance between +/-5 to 10 seconds per day, though some report better. A lack of screw-down crown and ISO certification are noted drawbacks for its water resistance. Some owners find the bracelet to be of cheaper construction with hollow links, and a few have reported quality control issues. The consensus is that the Seiko 5 Sports SKX series offers good value for its price, appealing to those who appreciate its tool-like nature and iconic lineage.

At a glance

11 of 29 specs differ
Diameter
Reef 42 mm42mm
5KX42.5mm
Power Reserve
Reef 42 mm56h
5KX41h
Water Resistance
Reef 42 mm300m
5KX100m
MSRP
Reef 42 mm$2,414
5KX$350

Full specifications

Case

4 specs
Diameter
42mm
42.5mm
Thickness
11.4mm
13.4mm
Lug-to-Lug
47mm
46mm
Water Resistance
300m
100m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
Dial Color
Black
Lume
Super-LumiNova
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Sellita SW300-1
4R36
Power Reserve
56h
41h
Jewels
0
24

Pricing

1 specs
MSRP
$2,414
$350
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