Side by side

Bremont Supermarine 300MvsIWC Schaffhausen Iw459403 Portofino Automatic Moon Phase

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.

Bremont Supermarine 300M

The Bremont Supermarine 300M is praised for its comfortable 40mm and 42mm case sizes, with owners noting the 42mm wears well on smaller wrists due to its lug design. One owner highlights the 13mm thinness of the 40mm case, considered compact for a 300m diver. The watch is priced at $1375. On balance, owners and reviewers appreciate the Bremont Supermarine 300M for its wearability and compact dimensions, especially for a dive watch.

IWC Schaffhausen Iw459403 Portofino Automatic Moon Phase

Owners widely praise the IWC Schaffhausen Portofino for its stunning and elegant design, with many finding the 40mm size wearability excellent, even on smaller wrists. The clean dial and classical sophistication are frequently highlighted, and some owners describe it as a "lifetime watch." One owner notes their watch keeps excellent time, with another mentioning IWC's commitment to chronometer standards. A different Portofino 37 variant was reported to lose almost 10 seconds a day. On balance, owners and reviewers rate the IWC Schaffhausen Portofino highly for its elegant design and comfortable wearability.

At a glance

15 of 29 specs differ
Diameter
Supermarine 300M40mm
Iw459403 Portofino Automatic Moon Phase40mm
Power Reserve
Supermarine 300M40h
Iw459403 Portofino Automatic Moon Phase50h
Water Resistance
Supermarine 300M300m
Iw459403 Portofino Automatic Moon Phase30m
MSRP
Supermarine 300M$3,550
Iw459403 Portofino Automatic Moon Phase$7,700

Full specifications

Case

6 specs
Category
Diver
Moonphase
Thickness
12mm
11.1mm
Material
904L Stainless Steel
Stainless Steel
Finish
Brushed and polished
18 ct 5N gold
Water Resistance
300m
30m
Caseback
Solid

Crystal & Dial

5 specs
Crystal
Sapphire
Crystal Shape
Flat
AR Coating
Inner
Dial Color
Green
Silver
Indices
Applied

Movement

3 specs
Caliber
BE-92AE
35800
Power Reserve
40h
50h
Complications
None
Moonphase

Pricing

1 specs
MSRP
$3,550
$7,700
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