Side by side

Serica Réf. 5303vsSeiko Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition

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.

Serica Réf. 5303

Owners widely praise the Serica Réf. 5303 for its unique neo-vintage design, sophisticated aesthetics, and excellent finishing, with many highlighting the smooth winding action and the tactile quality of the bezel click as industry-benchmark. The 39mm case is frequently cited as well-proportioned and wearable, especially for smaller wrists. Accuracy figures vary, with one owner reporting +2 seconds per day and another +5.5 seconds per day, while the 42-hour power reserve was noted as a point of desire for longer duration. Some owners have reported significant quality control issues, including dial shifting, non-functional hacking, and misaligned or jammed bezels, with concerns also raised about the Soprod movement and the manufacturer's communication. Overall, owners rate the Serica Réf. 5303 highly for its distinctive design and refined finishing, despite some significant quality control concerns raised by a few.

From video reviewers

The COSC and Grand Chronomètre Serica® certifications are a significant strength. No shared weaknesses were identified.

Seiko Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition

The Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition is praised for its compact 40mm case and the new Caliber 6R55 movement offering a 72-hour power reserve. Owners and reviewers highlight the stunning dials as a strong suit for Seiko. However, the 6R movement's accuracy is a point of disappointment for some, who wish for improvements closer to other movements, though others accept it given the excellent overall package. Press images suggest the bracelet end links may appear disjointed. Overall, owners and reviewers rate the Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition well, with the stunning dials and improved power reserve being the biggest reasons.

At a glance

12 of 29 specs differ
Diameter
Réf. 530339mm
Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition40mm
Power Reserve
Réf. 530342h
Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition72h
Water Resistance
Réf. 5303300m
Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition300m
MSRP
Réf. 5303$1,857
Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition$1,400

Full specifications

Case

4 specs
Category
Diver
Diameter
39mm
40mm
Thickness
12.2mm
13mm
Lug-to-Lug
46.5mm
46.4mm

Crystal & Dial

4 specs
Crystal Shape
Curved
AR Coating
Anti-reflective coating on inner surface
Dial Color
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Soprod M100
Seiko 6R55
Power Reserve
42h
72h
Jewels
0
24

Pricing

1 specs
MSRP
$1,857
$1,400
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