Side by side

Phoibos LeviathanvsGrand Seiko SLGA001

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

The bottom line

The 40mm Leviathan wears 6.9mm narrower than the 46.9mm SLGA001 — that's a meaningful jump on most wrists.

What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Phoibos Leviathan

Owners widely praise the Phoibos Leviathan for its excellent value, superb case finishing, and generous lume. The watch is described as visually striking, legible, and well-made, with a unique case design, sapphire crystal, and a comfortable FKM strap or excellent bracelet with a milled clasp and quick adjustments. Some owners note the bezel's staggered jimping can cause fingers to slip, and the beveled crystal can distort the view of indices. Accuracy varies, with one owner reporting losing 5-10 seconds per day without a winder, while others state it keeps accurate time out of the box. The watch is frequently described as heavy and thick, with some owners finding it too large for wrists smaller than 7.5 inches, although newer models feature an improved clasp for better comfort and functionality. Overall, owners rate the Phoibos Leviathan highly for its striking design and impressive finishing at an accessible price point.

Grand Seiko SLGA001

The Grand Seiko SLGA001 is praised for its impressive technical achievements, including a new, slimmer Spring Drive movement with a five-day power reserve and exceptional accuracy of ±0.5 seconds per day. Reviewers note the 47mm titanium case, despite its substantial dimensions, wears more comfortably due to its titanium construction, short lugs, and virtually scratch-proof finish. The watch features a 600-meter water resistance and is limited to 700 pieces, priced at $11,100. On balance, reviewers consider the Grand Seiko SLGA001 a highly capable dive watch, with its technological advancements in the Spring Drive movement being a key highlight.

From video reviewers

The watch's Spring Drive movement, specifically the Cal.9RA5, offers a 120-hour power reserve. A notable trade-off is the watch's relatively large size, with a case diameter of 46.9mm and thickness of 16.0mm, which may not suit those with smaller wrists. The high price point may be a trade-off for some buyers.

Where to get them

Check prices & track

Phoibos Leviathan
Phoibos Leviathan
MSRP $399
Grand Seiko SLGA001
Grand Seiko SLGA001
MSRP $11,100
Leviathan
PhoibosLeviathan
MSRP $399
SLGA001
Grand SeikoSLGA001
MSRP $11,100

At a glance

12 of 29 specs differ
Diameter
Leviathan40mm
SLGA00146.9mm
Power Reserve
Leviathan40h
SLGA001120h
Water Resistance
Leviathan200m
SLGA001100m
MSRP
Leviathan$399
SLGA001$11,100

Full specifications

Case

6 specs
Diameter
40mm
46.9mm
Thickness
13mm
16mm
Lug-to-Lug
48mm
50.8mm
Lug Width
20mm
23mm
Material
Stainless Steel
Titanium
Water Resistance
200m
100m

Crystal & Dial

2 specs
AR Coating
Yes
Inner
Lume
Super-LumiNova
None

Movement

3 specs
Caliber
SII NH35
9RA5
Type
Automatic
Spring Drive
Power Reserve
40h
120h

Pricing

1 specs
MSRP
$399
$11,100

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