Seiko 5KXvsWhitby Watch Co. Ad Mare Diver

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Measurements

Catalog photos are all shot at the same flattering size. These aren't: every case below shares one millimeter scale.

Seiko 5KX at true scale

5KX

Whitby Watch Co. Ad Mare Diver at true scale

Ad Mare Diver

Diameter

42.5mm

44mm

Lug-to-Lug

46mm

lowest

50.8mm

Thickness

13.4mm

lowest

14mm

Water Resistance

100m

200m

highest

Power Reserve

41h

highest

38h

MSRP

$350

lowest

$550

Movement

Seiko 4R36

Sellita SW200-1

Case

4 specs
Diameter
42.5mm
44mm
Thickness
13.4mm
14mm
Lug-to-Lug
46mm
50.8mm
Water Resistance
100m
200m

Crystal & Dial

3 specs
Crystal
Hardlex
Sapphire
Dial Color
Blue
n/a
Lume
LumiBrite on hands and index(es)
None

Movement

3 specs
Caliber
Seiko 4R36
Sellita SW200-1
Power Reserve
41h
38h
Jewels
24
0

Pricing

1 specs
MSRP
$350
$550
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Reviews

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

Seiko 5KX

Owners widely praise the Seiko 5KX for its strong lume and value, with many reporting accuracy within +/-5 to 10 seconds per day, though some experience +/-1 second. The 42.5mm case is noted to wear smaller, and the watch offers a comfortable feel for many. Some owners are split on the bracelet quality, with opinions ranging from "cheaper side" with hollow links to "flimsy-feeling" jubilee. A few quality control issues have been reported, including a failed bezel clickspring and misaligned components. The Seiko 5KX is seen by some as a worthy successor to the original SKX, offering an upgraded movement with hacking and hand-winding capabilities, though others lament the loss of ISO certification and a screw-down crown. Overall, owners rate the Seiko 5KX highly for its excellent lume and value proposition, making it a popular choice for everyday wear.

Whitby Watch Co. Ad Mare Diver

Owners widely praise the Whitby Watch Co. Ad Mare Dive Watch as a solid dive watch for its price, with multiple users calling it the best deal under $600 and one rating it 8.5 out of 10. Reviewers note its substantial feel, quality construction, and crisp dial with applied indices, powered by a Sellita SW200-1 automatic movement. Some owners find the 44mm case size to be a comfortable daily wear, with one mentioning the sanded texture of the titanium variant keeps it light. Drawbacks noted by one owner include the absence of a date wheel. Overall, owners and reviewers rate the Whitby Watch Co. Ad Mare Dive Watch highly for its value and build quality at its price point.