Side by side

Borealis Watch Co. Estoril 300 GMTvsSeiko Prospex Sea

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

Estoril 300 GMT
Borealis Watch Co.Estoril 300 GMT
MSRP $600
Prospex Sea
SeikoProspex Sea
MSRP $1,500

At a glance

12 of 29 specs differ
Diameter
Estoril 300 GMT41.50mm
Prospex Sea43.5mm
Power Reserve
Estoril 300 GMT40h
Prospex Sea70h
Water Resistance
Estoril 300 GMT300m
Prospex Sea200m
MSRP
Estoril 300 GMT$600
Prospex Sea$1,500

Full specifications

Case

6 specs
Diameter
41.50mm
43.5mm
Thickness
13.5mm
13.3mm
Lug-to-Lug
47mm
51mm
Lug Width
20mm
22mm
Material
Stainless Steel
Titanium
Water Resistance
300m
200m

Crystal & Dial

2 specs
AR Coating
Inner
Anti-reflective coating on inner surface
Lume
BGW9
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Miyota 9075
6R35
Power Reserve
40h
70h
Jewels
25
24

Pricing

1 specs
MSRP
$600
$1,500

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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.

Borealis Watch Co. Estoril 300 GMT

Owners widely praise the Borealis Watch Co. Estoril 300 GMT for its excellent value, robust build quality, and crisp dial, with reviewers highlighting its exceptionally bright BGW9 lume and dive-ready ceramic bezel. Some owners appreciate the brushed and polished finishes, though one owner noted a desire for a white-painted second hand. The included NATO strap is considered too thick with a loose weave, and the sapphire bezel insert is seen by some as a minor aesthetic departure from its inspirations. Overall, owners rate the Borealis Watch Co. Estoril 300 GMT highly for its impressive build quality and value.

Seiko Prospex Sea

Seiko Prospex Sea owners and reviewers praise its Marinemaster-style aesthetic, excellent case finishing, and impressive LumiBrite lume. The watch is powered by the 6R15 movement with a 50-hour power reserve and comes with both a steel bracelet and a silicone strap. Some owners find the Seiko Prospex Sea to be a great value and a suitable first "proper" watch, while others report it is uncomfortably big, thick, and heavy on smaller wrists. Reviewers note the GMT function is secondary with a less prominent scale, and the bezel's quieter clicks may not appeal to all. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its classic design and finishing at its price point.

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