Which is cheaper, the Marathon Arctic OSAR 46mm Automatic or the Seiko Prospex SPEEDTIMER Mechanical?

At MSRP the Seiko Prospex SPEEDTIMER Mechanical is the cheaper of the two at $995, against $2,500 for the Marathon Arctic OSAR 46mm Automatic — a $1,505 gap before any retailer discounting.

Which is bigger, the Marathon Arctic OSAR 46mm Automatic or the Seiko Prospex SPEEDTIMER Mechanical?

The Marathon Arctic OSAR 46mm Automatic wears larger at 46mm versus 39.5mm for the Seiko Prospex SPEEDTIMER Mechanical — a 6.5mm difference across the dial.

Which has better water resistance, the Marathon Arctic OSAR 46mm Automatic or the Seiko Prospex SPEEDTIMER Mechanical?

The Marathon Arctic OSAR 46mm Automatic is rated to 300m versus 20m for the Seiko Prospex SPEEDTIMER Mechanical.

Which has a longer power reserve, the Marathon Arctic OSAR 46mm Automatic or the Seiko Prospex SPEEDTIMER Mechanical?

The Seiko Prospex SPEEDTIMER Mechanical carries a 72-hour power reserve against 40 hours on the Marathon Arctic OSAR 46mm Automatic.

What movement does the Marathon Arctic OSAR 46mm Automatic run compared to the Seiko Prospex SPEEDTIMER Mechanical?

Both watches run automatic movements — the Marathon Arctic OSAR 46mm Automatic uses the Sellita SW220-1 and the Seiko Prospex SPEEDTIMER Mechanical uses the 6R55.

Side by side

Marathon Arctic OSAR 46mm AutomaticvsSeiko Prospex SPEEDTIMER Mechanical

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

Marathon Arctic OSAR 46mm Automatic

46mm-arctic-original-sar-w-date-on-3-piece-rubber-strap-kit-osar-d

MSRP $2,500

Seiko Prospex SPEEDTIMER Mechanical

spb513j1

MSRP $995

At a glance

15 of 29 specs differ

Diameter

Arctic OSAR 46mm Automatic46mm

Prospex SPEEDTIMER Mechanical39.5mm

Power Reserve

Arctic OSAR 46mm Automatic40h

Prospex SPEEDTIMER Mechanical72h

Water Resistance

Arctic OSAR 46mm Automatic300m

Prospex SPEEDTIMER Mechanical200m

MSRP

Arctic OSAR 46mm Automatic$2,500

Prospex SPEEDTIMER Mechanical$995

Full specifications

Case

7 specs

Crystal & Dial

4 specs

Crystal Shape

Flat

Curved

AR Coating

Inner

Anti-reflective coating on inner surface

Dial Color

White

Black

Lume

None

LumiBrite on hands and index(es)

Movement

3 specs

Caliber

Sellita SW220-1

6R55

Power Reserve

40h

72h

Jewels

Pricing

1 specs

MSRP

$2,500

$995

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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.

Marathon Arctic OSAR 46mm Automatic

Owners widely praise the Marathon Arctic OSAR 46mm Automatic for its overbuilt toughness and industrial, instrument-like aesthetic, with some preferring the Arctic dial for legibility. One owner notes the automatic movement may be unnecessary for rough use compared to a quartz option. Reviewers mention the MaraGlo luminous paint and a Sellita SW200-1 automatic movement. Some owners question its rising price and luxury positioning, with one reporting poor lume and movement performance. Overall, owners value the Marathon Arctic OSAR 46mm Automatic for its robust build and utilitarian design.

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Seiko Prospex SPEEDTIMER Mechanical

The Seiko Prospex SPEEDTIMER Mechanical is praised for its visually appealing design and comfortable wearability, with owners frequently using its chronograph function for daily tasks. Reviewers note its clean dial layout and LumiBrite treated hands and markers, and one source highlights the 72-hour power reserve of the 6R55 movement. However, some owners criticize its chronograph functionality and the 24-hour subdial. On balance, owners and reviewers rate the Seiko Prospex SPEEDTIMER Mechanical highly for its daily usability and refined aesthetics.

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