Side by side

Formex Reef 42 mmvsSinn U1 S L

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

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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.

Sinn U1 S L

The Sinn U1 S L is widely praised for its intense, full-lume dial, a feature described as new technology that glows brightly, and its unique black and white "arctic tactical" aesthetic. Owners and reviewers consistently highlight the Tegimented German submarine steel case for its exceptional scratch resistance and matte, non-reflective finish, with one owner reporting no scratches on the case after 17 years. The watch is also noted for its legibility and robust build, offering 1000m water resistance. However, some owners find the 44mm size and 14.7mm thickness wear large, and one reviewer noted the 4 o'clock crown positions lacked distinct clicks, leading to difficult date changes. Accuracy figures for the ETA 2824-2 movement vary, with one owner seeing +1/+2 s/day and another about -6 s/day. The Tegimented bracelet is reported to scratch more easily than the case by some, while others found it held up well.

At a glance

15 of 29 specs differ
Diameter
Reef 42 mm42mm
U1 S L44mm
Power Reserve
Reef 42 mm56h
U1 S L38h
Water Resistance
Reef 42 mm300m
U1 S L1,000m
MSRP
Reef 42 mm$2,414
U1 S L$3,532

Full specifications

Case

6 specs
Diameter
42mm
44mm
Thickness
11.4mm
14.7mm
Lug-to-Lug
47mm
Finish
black
Water Resistance
300m
1000m
Caseback

Crystal & Dial

4 specs
Crystal Shape
AR Coating
Underside
Indices
Lume
Super-LumiNova
Luminescent

Movement

4 specs
Caliber
Sellita SW300-1
Sellita SW200-1
Beat Rate
0 vph
28,800 vph
Power Reserve
56h
38h
Jewels
0
26

Pricing

1 specs
MSRP
$2,414
$3,532
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