Side by side

Borealis Watch Co. Estoril 300 GMTvsGrand Seiko SBGA427

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
SBGA427
Grand SeikoSBGA427
MSRP $5,800
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.

Grand Seiko SBGA427

Grand Seiko SBGA427 owners widely praise its extensive Zaratsu polishing and the "hall of mirrors" effect created by its diamond-cut indexes, complemented by a subtle, reeded dial and a striking green seconds hand. The 39mm case is noted for its comfortable, tapered bracelet, and the 9R65 Spring Drive movement is visible through the caseback. Some owners report the highly polished Zaratsu finish is prone to scuffs and scratches, with one mentioning a scratch near 1 o'clock. The Grand Seiko SBGA427 sold for $3750. Overall, owners rate the Grand Seiko SBGA427 highly for its exceptional finishing and the unique visual appeal of its dial and indexes.

At a glance

12 of 29 specs differ
Diameter
Estoril 300 GMT41.50mm
SBGA42739mm
Power Reserve
Estoril 300 GMT40h
SBGA42772h
Water Resistance
Estoril 300 GMT300m
SBGA427100m
MSRP
Estoril 300 GMT$600
SBGA427$5,800

Full specifications

Case

6 specs
Category
Diver
Dress
Diameter
41.50mm
39mm
Thickness
13.5mm
12.3mm
Lug-to-Lug
47mm
46.8mm
Lug Width
20mm
19mm
Water Resistance
300m
100m

Crystal & Dial

2 specs
AR Coating
Inner
Yes
Lume
BGW9
None

Movement

3 specs
Caliber
Miyota 9075
9R65
Type
Automatic
Spring Drive
Power Reserve
40h
72h

Pricing

1 specs
MSRP
$600
$5,800
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