Side by side

Formex Reef 39.5 mmvsSpinnaker Cahill Automatic

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

Reef 39.5 mm
FormexReef 39.5 mm
MSRP $2,230
Cahill Automatic
SpinnakerCahill Automatic
MSRP $350

At a glance

10 of 29 specs differ
Diameter
Reef 39.5 mm39.5mm
Cahill Automatic42mm
Power Reserve
Reef 39.5 mm56h
Cahill Automatic40h
Water Resistance
Reef 39.5 mm300m
Cahill Automatic200m
MSRP
Reef 39.5 mm$2,230
Cahill Automatic$350

Full specifications

Case

5 specs
Diameter
39.5mm
42mm
Thickness
11mm
13.7mm
Lug-to-Lug
45.5mm
51mm
Material
Stainless Steel
316L Stainless Steel
Water Resistance
300m
200m

Crystal & Dial

2 specs
Dial Color
Bahama Blue
Green
Lume
Super-LumiNova
None

Movement

2 specs
Caliber
Sellita SW300-1
SII NH35A
Power Reserve
56h
40h

Pricing

1 specs
MSRP
$2,230
$350

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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 39.5 mm

The Formex Reef 39.5 mm is widely praised for its refined finishing, comfortable and well-proportioned case design, and impressive specifications for its price point, including COSC-certified Sellita SW300-1 movement and 300m water resistance. Owners and reviewers highlight the tool-less micro-adjust clasp and quick-release spring bars as practical features. Some reviewers note that the 22mm lug width feels slightly disproportionate to the smaller case, and the bracelet could benefit from more taper, though this is a point of contention for some owners who value the overall package. A prototype crown protrusion issue is noted as being addressed for production. On balance, owners and reviewers rate the Formex Reef 39.5 mm highly for its excellent value and well-executed design.

Spinnaker Cahill Automatic

Owners widely praise the Spinnaker Cahill Automatic for its attractive vintage-inspired design, comfortable wearability on smaller wrists, and good timekeeping, with one owner specifically noting the large "maxi" indices and NATO strap as highlights. However, some find the lume application uneven and note the use of a mineral crystal. A significant concern raised by one owner is a report of internal component failures and a perceived lack of quality control within the brand. On balance, the Spinnaker Cahill Automatic is well-regarded by owners for its style and value, particularly at specific price points, despite some noted manufacturing inconsistencies.

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