Side by side

Orient M-Force AC0NvsSeiko Prospex Sea

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.

Orient M-Force AC0N

Owners widely praise the Orient M-Force AC0N for its rugged, tank-like appearance and robust, well-built construction, with many citing the reliability of Japanese automatic movements as a key draw. Reviewers and owners consistently flag excellent lume and a superior diver bezel, though one owner notes poor low-light legibility due to weak lume. Accuracy figures vary, with one owner reporting stable +12 seconds/day timekeeping while another found it kept near-perfect time when fully wound; a wobbly crown was also noted by one owner. Overall, owners rate the Orient M-Force AC0N highly for its toughness and value, with its striking design and durable build being the primary reasons for satisfaction.

Seiko Prospex Sea

The Seiko Prospex Sea is widely praised for its excellent value, solid build quality, and comfortable wearability, with many models featuring impressive lume and attractive dials. Owners and reviewers highlight the modern upgrades on classic designs, such as drilled lugs and reliable movements with hacking and hand-winding capabilities. Some models are noted for their refined case finishing and scratch resistance. Accuracy figures vary, with one owner reporting approximately 4 seconds fast per day, while others find the movements offer good performance for the price. Concerns raised by owners and reviewers include clasps that can feel generic or cheap, and lug widths that some find disproportionate to the case size on certain models. The thickness and weight of some Prospex Sea watches are also noted as substantial. The GMT function on specific models is considered secondary and difficult to read for true travel purposes.

At a glance

14 of 29 specs differ
Diameter
M-Force AC0N45mm
Prospex Sea43.8mm
Power Reserve
M-Force AC0N40h
Prospex Sea41h
Water Resistance
M-Force AC0N200m
Prospex Sea200m
MSRP
M-Force AC0N$555
Prospex Sea$625

Full specifications

Case

3 specs
Diameter
45mm
43.8mm
Lug-to-Lug
52mm
48.7mm
Lug Width
20mm
22mm

Crystal & Dial

3 specs
AR Coating
Underside
Anti-reflective coating on inner surface
Dial Color
Green
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

7 specs
Caliber
F6727
4R35
Beat Rate
21,600 vph
0 vph
Power Reserve
40h
41h
Jewels
22
23
Hacking
Yes
No
Hand-winding
Yes
No
Complications
Date
None

Pricing

1 specs
MSRP
$555
$625
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